Embryo Mosaicism: What You Need to Know

In 2005, my associate Levent Keskintepe PhD and I introduced Preimplantation Genetic Screening (PGS) with the ability to identify all chromosomes in the embryo’s cells, into the field of IVF.

This approach, which is now widely used throughout the world, permits selection of those embryos that are most likely to be competent, and has dramatically improved IVF success rates.

However, some abnormal (or aneuploid) embryos are capable of autocorrecting and reverting to a normal karyotype (euploid) during intrauterine development and of then propagating healthy babies. This is because some embryos can harbor both aneuploid AND euploid cells. This combination of aneuploid plus euploid cells in the same embryo is referred to as “mosaicism.”

It is an indisputable fact that many mosaic embryos further cell replication can result in the euploid cell component predominating ultimately resulting in a healthy conceptus. In many cases it is not possible to identify embryo “mosaicism”. Accordingly, we tend to preserve certain aneuploid embryos and recommend that they be transferred.

Once pregnant chorionic villus sampling (CVS) or amniocentesis should be done to determine the normalcy of the pregnancy, providing the patient(s) with the opportunity to terminate such pregnancies if they so choose. Join me tomorrow at 1:00PM PST on my Facebook page, as I address the pros and cons of preserving versus discarding all aneuploid embryos and define my policy in advising such patients.

87 Comments

Sophie

Hi Dr. Sher,
We have one pgs tested segmental mosaic egg.
5AB 4q delation (about 30-40%) and 5p duplication (about 60%)

Do you think there is a chance this egg leads to be a healthy baby?

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Ethan

Dr. Sher,

We have a Mosiac embryo that is a monosomy -5 and -10 High complex. Is this okay to transfer and is the viable pregnancy about 17 percent? Thank you!

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Dr. Geoffrey Sher

In my opinion, with >1 chromosome involved this is not likely to be a “mosaic” sand I would personally advise against transfering it.

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

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Mary Ann K

Dr. Sher, I am 43 years old and did an IVF retrieval in August ’18 that resulted in 2 PGS abnormal embryos (48, XX, 14, 19, MitoSure 0.72 which was a 3BB grade embryo and a 47, XX, 15, 19, -20, MitoSure 2.0 which was a 2BB grade embryo). I do not have DOR (My AMH ranges 1.6-1.9 and FSH ranges from 3-7 and I have normal cycles). We just did a second retreival this month of October and we find out Thursday if we got any blasts for a frozen transfer this December. We plan to NOT do PGS testing this cycle. I do also have elevated Natural Killer cells which I am in the process of figuring out how to control.
1) Are either of the two embryos I mentioned a candidate for transferring? Or are they “grossly abnormal” and will likely not correct?
2) Is the PGS research telling us that the PGS test result can be incorrect, or is it that the test was correctly testing abnormal, but it can correct itself?
3) Am I making a smart decision to not test my embryos I get from this current retrieval? I am thinking if I don’t test as least I will give them a fair chance.
4) I know it is not something you can say 100% to, but in your experience do you think if I did a few more retrievals it is possible I could get some normal embryos? Or are grossly abnormal embryos telling of future grossly abnormal embryos?
Thank you so much for your time.
Mary Ann

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Tasha Davis

Good Afternoon,
Embryos I have left are :

1) 45, XY -16
2)48, XX 4, 16

Can you tell me in your opinion which one you would transfer?

Thank You

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Mili

Hi Dr Sher,

We have 3 abnormal embryos and I’m curious if you would transfer any of these:

1) trisomy 4 (blastocyst)
2) monosomy 2 & 8 (blastocyst)
3) trisomy 15 and 22 (hatching blastocyst)

Thank you so much!

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Dr. Geoffrey Sher

There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

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Raania

Thanks for your reply.Do you think that these embryos have a chance to be mosaic and would have the possibility to autocorrect themselves? Would you do a transfer of such embryos? #1 21,#2 3 and one with fish result XO,-13,-18,-21,-21

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Raania

I’m 37 and just did an ivf.They give me Gonal F450 and then retrieve 5eggs one immature and remaining 3 fertilised and at day 3 they all looked great.they biopsy on day 3 and I got the PGS report today all 3 are abnormal #1- 21,#2 3 and one they do fish result XO,-13,-18,-21,-21
They are now at morula stage and tomorrow will be day 5.Embrologist told us that all are looking good and they will do the NGS testing again on day 5.SO Dr what do you think about my case and reliability of my test?I’ve done the procedure in dubai.
I’ve 11 to 12 resting follicles on my baseline scan,AMH 1.76 ng/ml now my Re is asking me to do another retrieval with same Gonal F dose and more time to give me after trigger shot so don’t face the eggs immaturity again So what should I do the next.
I have missed miscarriage in December due to trisomy 21 so that’s why I’m doing NGS but my Re do the test on day 3 embryos but after my results and embryos progress they are doing biopsy again.Please give me your opinion .

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Dr. Geoffrey Sher

In my opinion, the protocol used for ovarian stimulation must be carefully reviewed and revised.

The potential for a woman’s eggs to undergo orderly development and maturation, while in large part being genetically determined can be profoundly influenced by the woman’s age, her “ovarian reserve” and proximity to menopause. It is also influenced by the protocol used for controlled ovarian stimulation (COH) which by fashioning the intra-ovarian hormonal environment, profoundly impacts egg development and maturation.
After the menarche (age at which menstruation starts) a monthly process of repeatedly processing eggs continues until the menopause, by which time most eggs will have been used up, and ovulation and menstruation cease. When the number of eggs remaining in the ovaries falls below a certain threshold, ovarian function starts to wane over a 5 to10-years. This time period is referred to as the climacteric. With the onset of the climacteric, blood Follicle Stimulating Hormone (FSH) and later also Luteinizing Hormone (LH) levels begin to rise…. at first slowly and then more rapidly, ultimately culminating in the complete cessation of ovulation and menstruation (i.e. menopause).
One of the early indications that the woman has entered the climacteric and that ovarian reserve is diminishing DOR) , is the detection of a basal blood FSH level above 9.0 MIU/ml and/ or an AMH level og <2.0ng/ml.
Prior to the changes that immediately precede ovulation, virtually all human eggs have 23 pairs (i.e. 46) of chromosomes. Thirty six to forty hours prior to ovulation, a surge occurs in the release of LH by the pituitary gland. One of the main e purposes of this LH surge is to cause the chromosomes in the egg to divide n half (to 23 in number) in order that once fertilized by a mature sperm ends up having 23 chromosomes) the resulting embryo will be back to having 46 chromosomes. A “competent” mature egg is one that has precisely 23 chromosomes, not any more or any less. It is largely the egg, rather than the sperm that determines the chromosomal integrity of the embryo and only an embryo that has a normal component of 46 chromosomes (i.e. euploid) is “competent” to develop into a healthy baby. If for any reason the final number of chromosomes in the egg is less or more than 23 (aneuploid), it will be incapable of propagating a euploid, “competent” embryo. Thus egg/embryo aneuploidy (“incompetence”) is the leading cause of human reproductive dysfunction which can manifest as: arrested embryo development and/or failed implantation (which often presents as infertility), early miscarriage or chromosomal birth defects (e.g. Down’s syndrome). While most aneuploid (“incompetent”) embryos often fail to produce a pregnancy, some do. However, most such pregnancies miscarry early on. On relatively rare occasions, depending on the chromosome pair involved, aneuploid embryos can develop into chromosomally defective babies (e.g. Down’s syndrome).
Up until a woman reaches her mid- thirties, at best, 1:2 of her eggs will likely be chromosomally normal. As she ages beyond her mid-thirties there will be a a progressive decline in egg quality such that by age 40 years only about 15%-20% of eggs are euploid and, by the time the woman reaches her mid-forties, less than 10% of her eggs are likely to be chromosomally normal. While most aneuploid embryos do appear to be microscopically abnormal under the light microscope, this is not invariably so. In fact, many aneuploid embryos a have a perfectly normal appearance under the microscope. This is why it is not possible to reliably differentiate between competent and incompetent embryos on the basis of their microscopic appearance (morphologic grade) alone.
The process of natural selection usually precludes most aneuploid embryos from attaching to the uterine lining. Those that do attach usually do so for such only a brief period of time. In such cases the woman often will not even experience a postponement of menstruation. There will be a transient rise in blood hCG levels but in most cases the woman will be unaware of even having conceived (i.e. a “chemical pregnancy”). Alternatively, an aneuploid embryo might attach for a period of a few weeks before being expelled (i.e. a “miscarriage”). Sometimes (fortunately rarely) an aneuploid embryo will develop into a viable baby that is born with a chromosomal birth defect (e.g. Down’s syndrome).
The fact that the incidence of embryo aneuploidy invariably increases with advancing age serves to explain why reproductive failure (“infertility”, miscarriages and birth defects), also increases as women get older.
It is an over-simplification to represent that diminishing ovarian reserve as evidenced by raised FSH blood levels (and other tests) and reduced response to stimulation with fertility drugs is a direct cause of “poor egg/ embryo quality”. This common misconception stems from the fact that poor embryo quality (“incompetence”) often occurs in women who at the same time, because of the advent of the climacteric also have elevated basal blood FSH/LH levels and reduced AMH. But it is not the elevation in FSH or the low AMH that causes embryo “incompetence”. Rather it is the effect of advancing age (the “biological clock”) resulting a progressive increase in the incidence of egg aneuploidy, which is responsible for declining egg quality. Simply stated, as women get older “wear and tear” on their eggs increases the likelihood of egg and thus embryo aneuploidy. It just so happens that the two precipitating factors often go hand in hand.
The importance of the IVF stimulation protocol on egg/embryo quality cannot be overstated. This factor seems often to be overlooked or discounted by those IVF practitioners who use a “one-size-fits-all” approach to ovarian stimulation. My experience is that the use of individualized/customized COS protocols can greatly improve IVF outcome in patients at risk – particularly those with diminished ovarian reserve (“poor responders”) and those who are “high responders” (women with PCOS , those with dysfunctional or absent ovulation, and young women under 25 years of age).
While no one can influence underlying genetics or turn back the clock on a woman’s age, any competent IVF specialist should be able to tailor the protocol for COS to meet the individual needs of the patient.
During the normal ovulation cycle, ovarian hormonal changes are regulated to avoid irregularities in production and interaction that could adversely influence follicle development and egg quality. As an example, small amounts of androgens (male hormones such as testosterone) that are produced by the ovarian stroma (the tissue surrounding ovarian follicles) during the pre-ovulatory phase of the cycle enhance late follicle development, estrogen production by the granulosa cells (cells that line the inner walls of follicles), and egg maturation.
However, over-production of testosterone can adversely influence the same processes. It follows that protocols for controlled ovarian stimulation (COS should be geared toward optimizing follicle growth and development (without placing the woman at risk from overstimulation), while at the same time avoiding excessive ovarian androgen production. Achievement of such objectives requires a very individualized approach to choosing the protocol for COS with fertility drugs as well as the precise timing of the “trigger shot” of hCG.
It is important to recognize that the pituitary gonadotropins, LH and FSH, while both playing a pivotal role in follicle development, have different primary sites of action in the ovary. The action of FSH is mainly directed towards the cells lining the inside of the follicle that are responsible for estrogen production. LH, on the other hand, acts primarily on the ovarian stroma to produce male hormones/ androgens (e.g. androstenedione and testosterone). A small amount of testosterone is necessary for optimal estrogen production. Over-production of such androgens can have a deleterious effect on granulosa cell activity, follicle growth/development, egg maturation, fertilization potential and subsequent embryo quality. Furthermore, excessive ovarian androgens can also compromise estrogen-induced endometrial growth and development.
In conditions such as polycystic ovarian syndrome (PCOS), which is characterized by increased blood LH levels, there is also increased ovarian androgen production. It is therefore not surprising that “poor egg/embryo quality” is often a feature of this condition. The use of LH-containing preparations such as Menopur further aggravates this effect. Thus we recommend using FSH-dominant products such as Follistim, Puregon, and Gonal-F in such cases. While it would seem prudent to limit LH exposure in all cases of COS, this appears to be more vital in older women, who tend to be more sensitive to LH
It is common practice to administer gonadotropin releasing hormone agonists (GnRHa) agonists such as Lupron, and, GnRH-antagonists such as Ganirelix and Orgalutron to prevent the release of LH during COS. GnRH agonists exert their LH-lowering effect over a number of days. They act by causing an initial outpouring followed by a depletion of pituitary gonadotropins. This results in the LH level falling to low concentrations, within 4-7 days, thereby establishing a relatively “LH-free environment”. GnRH Antagonists, on the other hand, act very rapidly (within a few hours) to block pituitary LH release, so as achieve the same effect.
Long Agonist (Lupron/Buserelin) Protocols: The most commonly prescribed protocol for Lupron/gonadotropin administration is the so-called “long protocol”. Here, Lupron is given, starting a week or so prior to menstruation. This results in an initial rise in FSH and LH level, which is rapidly followed by a precipitous fall to near zero. It is followed by uterine withdrawal bleeding (menstruation), whereupon gonadotropin treatment is initiated while daily Lupron injections continue, to ensure a “low LH” environment. A modification to the long protocol which I prefer using in cases of DOR, is the Agonist/Antagonist Conversion Protocol (A/ACP) where, upon the onset of a Lupron-induced bleed , this agonist is supplanted by an antagonist (Ganirelix/Cetrotide/Orgalutron) and this is continued until the hCG trigger. In many such cases I supplement with human growth hormone (HGH) to try and further enhance response and egg development.
Lupron Flare/Micro-Flare Protocol: Another approach to COS is by way of so-called “(micro) flare protocols”. This involves initiating gonadotropin therapy simultaneous with the administration of GnRH agonist (e.g. Lupron/Buserelin). The intent here is to deliberately allow Lupron to elicit an initial surge (“flare”) in pituitary FSH release in order to augment FSH administration by increased FSH production. Unfortunately, this “spring board effect” represents “a double edged sword” because while it indeed increases the release of FSH, it at the same time causes a surge in LH release. The latter can evoke excessive ovarian stromal androgen production which could potentially compromise egg quality, especially in older women and women with PCOS, whose ovaries have increased sensitivity to LH. I am of the opinion that by evoking an exaggerated ovarian androgen response, such “(micro) flare protocols” can harm egg/embryo quality and reduce IVF success rates, especially in older women, and in women with diminished ovarian reserve. Accordingly, I do not prescribe them at all.
Estrogen Priming – My approach for “Poor Responders” Our patients who have demonstrated reduced ovarian response to COS as well as those who by way of significantly raised FSH blood levels are likely to be “poor responders”, are treated using a “modified” long protocol. The approach involves the initial administration of GnRH agonist for a number of days to cause pituitary down-regulation. Upon menstruation and confirmation by ultrasound and measurement of blood estradiol levels that adequate ovarian suppression has been achieved, the dosage of GnRH agonist is drastically lowered and the woman is given twice-weekly injections of estradiol for a period of 8. COS is thereupon initiated using a relatively high dosage of FSH-(Follistim, Bravelle, Puregon or Gonal F) which is continued along with daily administration of GnRH agonist until the “hCG trigger.” By this approach we have been able to significantly improve ovarian response to gonadotropins in many of hitherto “resistant patients”.
The “Trigger”: hCG (Profasi/Pregnyl/Novarel) versus Lupron: With ovulation induction using fertility drugs, the administration of 10,000U hCGu (the hCG “trigger”) mimics the LH surge, sending the eggs (which up to that point are immature (M1) and have 46 chromosomes) into maturational division (meiosis) This process is designed to halve the chromosome number , resulting in mature eggs (M2) that will have 23 chromosomes rather that the 46 chromosomes it had prior to the “trigger”. Such a chromosomally normal, M2 egg, upon being fertilized by mature sperm (that following maturational division also has 23 chromosomes) will hopefully propagate embryos that have 46 chromosomes and will be “:competent” to propagate viable pregnancies. The key is to trigger with no less than 10,000U of hCGu (Profasi/Novarel/Pregnyl) and if hCGr (Ovidrel) is used, to make sure that 500mcg (rather than 250mcg) is administered. In my opinion, any lesser dosage will reduce the efficiency of meiosis, and increase the risk of the eggs being chromosomally abnormal. . I also do not use the agonist (Lupron) “trigger”. This approach which is often recommended for women at risk of overstimulation, is intended to reduce the risk of OHSS. The reason for using the Lupron trigger is that by inducing a surge in the release of LH by the pituitary gland it reduces the risk of OHSS. This is true, but this comes at the expense of egg quality because the extent of the induced LH surge varies and if too little LH is released, meiosis can be compromised, thereby increasing the percentage of chromosomally abnormal and of immature (M1) eggs. The use of “coasting” in such cases) can obviate this effect
.I strongly recommend that you visit http://www.DrGeoffreySherIVF.com. Then go to my Blog and access the “search bar”. Type in the titles of any/all of the articles listed below, one by one. “Click” and you will immediately be taken to those you select. Please also take the time to post any questions or comments with the full expectation that I will (as always) respond promptly.

• The IVF Journey: The importance of “Planning the Trip” Before Taking the Ride”
• Controlled Ovarian Stimulation (COS) for IVF: Selecting the ideal protocol
• The Fundamental Requirements For Achieving Optimal IVF Success
• Use of GnRH Antagonists (Ganirelix/Cetrotide/Orgalutron) in IVF-Ovarian Stimulation Protocols.
• Anti Mullerian Hormone (AMH) Measurement to Assess Ovarian Reserve and Design the Optimal Protocol for Controlled Ovarian Stimulation (COS) in IVF.
• The “Biological Clock” and how it should Influence the Selection and Design of Ovarian Stimulation Protocols for IVF.
• A Rational Basis for selecting Controlled Ovarian Stimulation (COS) protocols in women with Diminished Ovarian Reserve (DOR)
• Diagnosing and Treating Infertility due to Diminished Ovarian Reserve (DOR)
• Ovarian Stimulation in Women Who have Diminished Ovarian Reserve (DOR): Introducing the Agonist/Antagonist Conversion protocol
• Controlled Ovarian Stimulation (COS) in Older women and Women who have Diminished Ovarian Reserve (DOR): A Rational Basis for Selecting a Stimulation Protocol
• Optimizing Response to Ovarian Stimulation in Women with Compromised Ovarian Response to Ovarian Stimulation: A Personal Approach.
• Egg Maturation in IVF: How Egg “Immaturity”, “Post-maturity” and “Dysmaturity” Influence IVF Outcome:
• Commonly Asked Question in IVF: “Why Did so Few of my Eggs Fertilize and, so Many Fail to Reach Blastocyst?”
• Human Growth Hormone Administration in IVF: Does it Enhances Egg/Embryo Quality and Outcome?
• The BCP: Does Launching a Cycle of Controlled Ovarian Stimulation (COS). Coming off the BCP Compromise Response?
• Staggered IVF
• Staggered IVF with PGS- Selection of “Competent” Embryos Greatly Enhances the Utility & Efficiency of IVF.
• Staggered IVF: An Excellent Option When. Advancing Age and Diminished Ovarian Reserve (DOR) Reduces IVF Success Rate
• Embryo Banking/Stockpiling: Slows the “Biological Clock” and offers a Selective Alternative to IVF-Egg Donation
• Preimplantation Genetic Testing (PGS) in IVF: It should be Used Selectively and NOT be Routine.
• IVF: Selecting the Best Quality Embryos to Transfer
• Preimplantation Genetic Sampling (PGS) Using: Next Generation Gene Sequencing (NGS): Method of Choice.
• PGS in IVF: Are Some Chromosomally abnormal Embryos Capable of Resulting in Normal Babies and Being Wrongly Discarded?
• PGS and Assessment of Egg/Embryo “competency”: How Method, Timing and Methodology Could Affect Reliability
• IVF outcome: How Does Advancing Age and Diminished Ovarian Reserve (DOR) Affect Egg/Embryo “Competency” and How Should the Problem be addressed.

If you are interested in my advice or medical services, I urge you to contact my patient concierge, ASAP to set up a Skype or an in-person consultation with me. You can also set this up by emailing concierge@sherivf.com or by calling 702-533-2691 and/or 800-780-743. You can also enroll for a consultation with me, online at http://www.SherIVF.com.
Also, my book, “In Vitro Fertilization, the ART of Making Babies” is available as a down-load through http://www.Amazon.com .

Geoffrey Sher MD

reply
Raania

Thanks for your spontaneous reply
Which one I can transfer in these ?trisomy 21 ,trisomy 3,XO -13,-18,-21,-21
And day 3 PGS testing can give false positives?

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Mario Flores Duhart

Hi doc we have a Partial Mosaic (28%) of -5 XY. Would you transfer it ? thanks

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Dr. Geoffrey Sher

Yes I would!

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

reply
Laurel Douglas

Thank you for your blog. This post gave me hope on a hard day. My husband and I are 36 and just completed our first round of IVF with PGD/PGS. Our son has cystic fibrosis, so we entered the IVF world for PGD. We found out today that all four of our embryos were abnormal, however one of them is a high level mosaic that is not affected by CF. The mosaic is -22. I have been reading a lot this evening, and I feel like there is a chance this embryo could lead to a healthy baby. Would you advise patient to attempt a transfer if this was their best option? Thank you.

reply
Dr. Geoffrey Sher

I would definitely transfer this embryo!

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

reply
Ana Maria Alonso Viola

Hello Dr Sher, I just finished my 3rd round of IVF and while PGS results showed 2 abnormal
We got one XX 2 (mos) low level mosaic. Would you recommend transferring? I am 39 years old and at this point can’t afford another IVF round.
Thank you so much!
Ana

reply
Dr. Geoffrey Sher

yes I would transfer it!

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Good luck!

Geoff Sher

reply
Jennifer

Hi Dr. Sher,

I’m wondering what your opinion is on possibly transferring the following frozen embryos:
1) monosomy 18
2) monosomy 16, trisomy 21, trisomy 22

I also have a day 5 embryo frozen that has not yet reached blastocyst (12 cell, grade BC) – what do you believe it’s chances of developing normally might be if transferred?

Thank you!

reply
Dr. Geoffrey Sher

I would only transfer the monosomy-18 embryo.

The one that is cleaved on day 5 is unlikely to make blastocyst by day 6…but I could be wrong.

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher
PH: 800-780-7437

reply
Holly

Hi Dr. Sher,

Would you consider transferring any of these mosaic embryos:

1.+5[mos], +17[mos] High Level
2.Dup (3)(q26.31-qter)[mos] Low Level
3.Del (7)(q11.23)[mos] High Level
4. Dup(6)(q14.1-qter) [mos]

Any insight is appreciated. Thanks!

reply
Dr. Geoffrey Sher

Hi Holly,

In my opinion, it is presently not possible to reliably identify which aneuploid embryos are “mosaic” versus meiotically aneuploid.

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

reply
Peter

Hi Dr Sher,
Thank you for such a comprehensive website and information.
I was hoping you might be able to provide a recommendation on our 2 mosaic embryos, would you suggest attempting to transfer these?
1: Mosaic for extra copy of 74mb region of chromosome 6 (6q15 q25.3)
2: Mosaic for extra copy of 29mb region of chromosome 16 (16p13.3 p11.2)
We understand the mosaic level to be approx 40-50%
Both my wife and I have had karyotype testing and have the correct number of chromosomes.

Any advice is appreciated, thank you.

Kind Regards,

Peter.

reply
Dr. Geoffrey Sher

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

reply
Jacqueline Higgins-Dailey

Hi Dr Sher, I have one female low-level mosaic embryo with a 5p deletion. Since this abnormality can result in Cri du Chat, I’ve been told not to transfer. What are your thoughts? I am 38 years old, stage IV endo (surgery two years ago) and have never been pregnant. All my other embryos were graded poor and complex aneuploid. This embryo was graded “fair.” Thank you.

reply
Dr. Geoffrey Sher

I agree! This m is a risk. However, in my opinion it can be diagnosed by CVS or amniocentesis once you are pregnant and thus I would do the transfer, provided you are resolute in a decision to terminate the pregnancy if it turns out to be a Cri du Chat.

Discuss with your RE.

Geoff Sher

reply
Jacqui

May I follow up and ask if you would consider transferring my two aneuploid embryos? Both rated poor. One is a -16 and +22 and the other is -11(mos) and -17.

Jacqui

Is it true that the CVS- because it’s from placenta- can show the same mosaicism and that only 23% of the mosaic results are present in birth. Basically there’s more often a false positive? That seems to make it hard to decide to terminate. What about an amnio in this case? Better odds of accuracy?

reply
Dr. Geoffrey Sher

“Mosaicism” encountered in CVS is unrelated to the fetal nymerical chromosomal integrity (karyotype) and as such is an inaccurate prediction of the fetal genetic make-up, the purpose of prenatal diagnosis. Most of the mosaicism detected in CVS is due to confined placental mosaicism.The higher frequency of discrepant results in direct CVS preparation emphasizes the prudence of delaying decision making until the results of the CVS culture have been obtained.

Although the observation of mosaicism clearly complicates genetic counseling and decision making, it does not appear to be associated with an adverse fetal outcome.Either CVS or an amnio, in my opinion, should thus be definitive.

Geoff Sher

reply
Jacqueline Higgins-Dailey

Okay- I think I understand- and I apologize, this is all new to me! But are you saying that the CVS would have to be aneuploid – not mosaic- in order for termination to be recommended? Does that make sense?

Amy

Hi Dr. Sher, thank you for your blog. It has really helped me navigate through treatment. This post subject is something I’ve not heard of from my doctor. I’m curious to know if should discard embryos that I have. I haven’t produced a PGS normal blastocyst yet, but wondered about these blastocysts:

1) Monosomy 15, Trisomy 19
2) Trisomy 3
3) Trisomy 14, Trisomy 21
4) Trisomy 13, Monosomy 21
5) Monosomy 16, Monosomy 19

Any insight is appreciated!

reply
Christene

Would you consider transferring any of the following blasts? Which would have the most potential?
1. 45, XY, -4,del(10)(q23), abnormal day 6 blast
2. 45, XX, -11, abnormal day 5 blast
3. 45, XX, -17, mosaic day 5 blast

Thank you!!

reply
Dr. Geoffrey Sher

All have a chance…in my opinion.

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

reply
nicole

Dr. Sher: We have a partial/segmental mosaic trisomy (+22q, dup 12.1qter) that has been designated “high level” 40%-80% but not more specific. I’ve read the studies saying any level of mosaicism has an equal chance of OP/LB. Do you think this is risky to transfer for LB of a child with 22+12.1 qter abnormalities? The GC at our university hospital clinic was not optimistic. We’ve had 6 losses after an unassisted normal pregnancy and tried IVF+PGS to avoid MC. We appreciate the knowledge of MC risk going into it & intend to do amnio if OP is achieved. Thank you.

reply
Dr. Geoffrey Sher

I probably would do the transfer.

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

reply
Esther

Have you ever transferred a monosomy 8, 14 or 16 that was not confirmed to be mosaic that resulted in a healthy live birth?

reply
Dr. Geoffrey Sher

There is in my opinion, no reliable way to differentiate between mosaicism and meiotic aneuploidy. So I would consider all/any of those embryos to potentially be mosaic”.

Geoff Sher

reply
Esther

Thank you! Have you personally ever transferred any of those type of embryos that produced a healthy live birth? What are the specific risks associated with transfer?

reply
Esther

To confirm, you would transfer any of the three monosomy 8, 14 and 16 non confirmed mosaic embryos? Would you skip confirmation for mosaicism? Would you prioritize an embryo over another re: the type of monosomy an embryo is? Or do all share the same potential?

Caroline Bahadourian

Hello Dr
After 3 retrievals at the age of 39
I’m now 10 weeks pregnant from a mosaic embryo with segmental monosomy
XY 6q23 del

My embryologist didn’t want me to transfer
Dr Kiltz from cny told
Me it could result into a healthy baby
Baby is growing well and measuring ahead
I really hope that I made the right choice
I couldn’t find anybody else who transferred an embryo with a deletion
All I see is monosomy le trisomy or dup’
Was it safe to transfer a mosaic embryo with a deletion on chromosome 6?

reply
Dr. Geoffrey Sher

I believe you made the right decision. I would however do a CVS or amniocentesis to confirm all is well.

Good luck!

Geoff Sher

reply
Kristin S

Greetings! After a failed FET with a euploid 4CB, we have a euploid 4BB blast on ice and are awaiting ERA results before planning another transfer. I also have a frozen aneuploid early blast 3BB +22. My lab reports mosaicism and did not see mosaicism in the +22 sample. What are your thoughts on eventually transferring the +22?

reply
Dr. Geoffrey Sher

I would consider having it transferred and then testing any resulting pregnancy for aneuploidy usingh chorionic villus sampling or amniocentesis. There is in my opinion no practical way to reliably differentiate between a meiotically aneuploid and a mosaic embryo with a single autosomal aneuploidy.

Geoff Sher

reply
Melody

Hello I was told after PGS we have an abnormal -17,-19 (said this particular one shows mosaic tendencies) and one abnormal -16 That did not show any signs of mosaicm. In your opinion should the one with the -17,-19 deletions be considered?

reply
Dr. Geoffrey Sher

In my opinion, given that b2 chromosomes are absent, this is less likely to be “mosaic”.

Currently, with very few exceptions, the vast majority of IVF programs demand of their patients undergoing IVF with full embryo karyotyping (total numerical chromosomal assessment) that those embryos found to be aneuploid (i.e. have an abnormal numerical chromosomal configuration) be would be discarded. This practice is prompted by the belief that such embryos would either fail to implant, be lost in early pregnancy or would propagate defective offspring (e.g. Down syndrome etc.).
Some would argue that chromosomally abnormal (aneuploid) embryos should be frozen and banked (cryostored) rather than be discarded. This argument is based on the fact that with progressive development, some aneuploid embryos will ultimately become chromosomally “competent” (euploid) and propagate healthy offspring. The process is referred to as “autocorrection” This position is founded on the fact that some embryos found through chromosomal testing (karyotyping or PGS) to harbor one or more aneuploid cell sometimes also harbor chromosomally normal (euploid) cells. This combination of aneuploid plus euploid cells in the same organism is referred to as mosaicism. It is an indisputable fact that in the case of many mosaic embryos further cell replication can result in the euploid cell component predominating ultimately resulting in a healthy conceptus. This article will address the pros and cons of preserving versus discarding all aneuploid embryos.
Introduction:
There are two varieties of embryo aneuploidy:
1. The first, “meiotic aneuploidy” which results from aberrations in chromosomal numerical configuration that originates in either the egg (most commonly) or in the sperm, during preconceptual maturational division (meiosis). Meiotic aneuploidy will thus be perpetuated in all cells of that embryo, rendering it permanently and irreversibly “incompetent” (incapable of propagating a normal pregnancy).
2. The second is “mitotic aneuploidy” which results when following fertilization and during subsequent cell replication (mitosis), mechanisms such as :
a. Nondisjunction: the failure of homologous chromosomes or sister chromatids to separate properly during cell division
b. Anaphase lag :slowing or arrest of the normal migration of chromosomes during anaphase)
c. Endoreplication : the replication of DNA during the S phase of the cell cycle without the subsequent completion of mitosis and/or cytokinesis and,
d. Sporadic mutation: a new mutation of a gene that was not inherited from either partners’ gamete (egg or sperm).
The above mechanisms can affect chromosomal replication in one or some (not all) of the embryo’s cells. With further embryo development, the karyotype of such cells is continually being perpetuated. Thereupon, with repeated, mitosis (by which all cells multiply after fertilization), some euploid cells will inevitably become aneuploid resulting in a blend of both aneuploid and euploid cells in the same tissue or organism (mosaicism). Whether or not the developing mosaic embryo/blastocyst/conceptus survives depends on the percentage of euploid versus aneuploid cells. If the aneuploidy is “overwhelming” the embryo will succumb …if not it might go on to develop into normal conceptus.
Since meiosis occurs in the pre-fertilized egg (usually) or in the sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection” from occurring and a healthy conceptus from developing.
Since some mitotically aneuploid (“mosaic”) embryos can “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between the two would be of enormous clinical value. The problem is that short of separately karyotyping all cells in an embryo (which inevitably would result in it being destroyed) there is presently no genetic test by which to distinguish between meiotic and mitotic aneuploidy. In any case, we presently do not know the percentage of mitotically aneuploid cells in an embryo, beyond which it would be rendered “incompetent” (i.e. the “aneuploidy threshold.
Some would argue that because aneuploid embryo cells (blastomeres) are more frequently detected in day 3 embryos than in blastocysts, that mosaicism must be more common in early day 3 embryos than in blastocysts, and that since some mosaic blastocysts can “autocorrect” and even go on to propagate a viable baby, the inability to confirm that aneuploidy is meiotic (irreversible) is an argument in favor of preserving all aneuploid embryos for future dispensation.
But consider the following:
1. Well above 50% (age dependent) of morphologically good looking (high grade), cleaved, day 3 embryos are aneuploid and the incidence increases to >90% by the time the woman reaches her mid-40’s.
2. We reported on a study where we biopsied and karyotyped each of 104 eggs (1st polar body). Thereupon, following in vitro fertilization, we performed a second biopsy (2nd polar body) on the day following fertilization. We again rebiopsied a single blastomere from all day 3 (cleaved) embryos) using a method known as metaphase CGH (mCGH).
The results of this study clearly demonstrated that in >95% of such cases the karyotype (numerical chromosome configuration) of the egg of origin was propagated linearly through the zygote and embryo and that in cases where the fertilized egg failed to develop into an expanded blastocyst, the egg of origin was almost always aneuploid (obviously meiotic). Since virtually all the day-3 embryos were derived from aneuploid eggs, it follows that they were meiotically, rather than mitotically aneuploid and thus “totally “incompetent”. We learned thereby that if you perform embryo karyotyping on day 3 rather than on blastocysts that through mitosis have progressed to the 100+ cell stage, you would have approximately 95%confidence that the embryo was meiotically (rather than mitotically) aneuploid…and thus doomed.
However, the above scenario only applies to the performance of karyotyping that is capable of accurately detecting aneuploidy from the minute amount of DNA present in a single cell (polar body or blastomere). Metaphase CGH (and possibly also a new method known as Next Generation Gene Sequencing) is required to this. Array CGH on the other hand requires access to much more DNA than is available from a single cell. That is why it is performed on hypercellular blastocysts rather than on early cleaved embryos. Blastocyst biopsy allows for the removal of several cells and the pooling of the DNA, thereby permitting a diagnosis of euploidy and aneuploidy.
It is true that when we transfer microscopically good quality embryos that have not been karyotyped to the uterus, many are aneuploid. However, in such cases we are not, with presence of forethought (knowingly) transferring defective embryos and thereby deliberately doing harm. Conversely, the deliberate transfer of embryos known through karyotyping to be aneuploid presents a vastly different moral/ethical dilemma. Here embryos known with a high level of confidence to be aneuploid would be transferred thus by definition we would knowingly be “doing harm”. This, in my opinion is a flagrant violation of the Hippocratic Oath and accordingly is something that we as well as most other centers that perform embryo karyotyping do not do. I say this with the full knowledge that in about 5% of cases we would be discarding mitotically aneuploid (mosaic) embryo that could theoretically have “autocorrected” and propagated a viable pregnancy.
Thus the message that I (with one regrettable exception) have consistently conveyed to my patients is that if karyotyping reveals one or more of their embryos to be aneuploid, and they to preserve such embryos rather than discard them…I will do so but I would not be willing to transfer them to the uterus. Instead we would willing to relocate them to a center of theirchoice for later dispensation as per their directive(s).

Geoff Sher

reply
Clara

Hello. Would you consider transferring a PGS tested embryo that is labeled “high level mosaic”
Dup (5)? Thanks!

reply
Kim

Dr. Sher, Thanks so much for your response, I truly appreciate it. However, after several failed IUIs and 2 rounds of IVF, I am not interested in going for a third round. So, these embryos are all I have to work with. Would you consider transferring any of them?
#1. XX – mosaic monosomy 11, mosaic trisomy 16
#2. XY – Mosaic Partial monosomy 8q21.2-qter
#3. XX – Dup(5)(p15.33-qter)(mos) – not exactly sure what it says in parenthesis on report
#4. XX – (-12, +15)
Thanks again!

reply
Kim

Hello!
I’m 42 years old, 2 rounds of IVF with a total of 21 embryos sent for PGS testing. Transfer of our only normal failed. What are your thoughts on the following mosaics? And in what order to transfer, if any?

#1. XX – mosaic monosomy 11, mosaic trisomy 16
#2. XY – Mosaic Partial monosomy 8q21.2-qter
#3. XX – Dup(5)(p15.33-qter)(mos) – not exactly sure what it says in parenthesis on report
#4. XX – (-12, +15)

Thanks so much!

reply
Dr. Geoffrey Sher

I really think you need to have your protocol for stimulation reassessed and possibly revised.

The older a woman becomes, the more likely it is that her eggs will be chromosomally/genetically “incompetent” (not have the potential upon being fertilized and transferred, to result in a viable pregnancy). That is why, the likelihood of failure to conceive, miscarrying and of giving birth to a chromosomally defective child (e.g. with Down Syndrome) increases with the woman’s advancing age. In addition, as women age beyond 35Y there is commonly a progressive diminution in the number of eggs left in the ovaries, i.e. diminished ovarian reserve (DOR). So it is that older women as well as those who (regardless of age) have DOR have a reduced potential for IVF success. Much of this is due to the fact that such women tend to have increased production of LH biological activity which can result in excessive LH-induced ovarian male hormone (predominantly testosterone) production which in turn can have a deleterious effect on egg/embryo “competency”.
While it is presently not possible by any means, to reverse the age-related effect on the woman’s “biological clock, certain ovarian stimulation regimes, by promoting excessive LH production (e.g. short agonist/Lupron- “flare” protocols, clomiphene and Letrozole), can make matters worse. Similarly, the amount/dosage of certain fertility drugs that contain LH/hCG (e.g. Menopur) can have a negative effect on the development of the eggs of older women and those who have DOR and should be limited.
I try to avoid using such protocols/regimes (especially) in older women and those with DOR, favoring instead the use of the agonist/antagonist conversion protocol (A/ACP), a modified, long pituitary down-regulation regime, augmented by adding supplementary human growth hormone (HGH). I further recommend that such women be offered access to embryo banking of PGS (next generation gene sequencing/NGS)-selected normal blastocysts, the subsequent selective transfer of which by allowing them to to capitalize on whatever residual ovarian reserve and egg quality might still exist and thereby “make hay while the sun still shines” could significantly enhance the opportunity to achieve a viable pregnancy
Please visit my new Blog on this very site, http://www.DrGeoffreySherIVF.com, find the “search bar” and type in the titles of any/all of the articles listed below, one by one. “Click” and you will immediately be taken to those you select. Please also take the time to post any questions or comments with the full expectation that I will (as always) respond promptly
• Controlled Ovarian Stimulation (COS) for IVF: Selecting the ideal protocol
• IVF: Factors Affecting Egg/Embryo “competency” during Controlled Ovarian Stimulation(COS)
• The Fundamental Requirements For Achieving Optimal IVF Success
• Ovarian Stimulation for IVF using GnRH Antagonists: Comparing the Agonist/Antagonist Conversion Protocol.(A/ACP) With the “Conventional” Antagonist Approach
• Anti Mullerian Hormone (AMH) Measurement to Assess Ovarian Reserve and Design the Optimal Protocol for Controlled Ovarian Stimulation (COS) in IVF.
• The “Biological Clock” and how it should Influence the Selection and Design of Ovarian Stimulation Protocols for IVF.
• A Rational Basis for selecting Controlled Ovarian Stimulation (COS) protocols in women with Diminished Ovarian Reserve (DOR)
• Diagnosing and Treating Infertility due to Diminished Ovarian Reserve (DOR)
• Controlled Ovarian Stimulation (COS) in Older women and Women who have Diminished Ovarian Reserve (DOR): A Rational Basis for Selecting a Stimulation Protocol
• Human Growth Hormone Administration in IVF: Does it Enhances Egg/Embryo Quality and Outcome?
• The BCP: Does Launching a Cycle of Controlled Ovarian Stimulation (COS). Coming off the BCP Compromise Response?
• Blastocyst Embryo Transfers Should be the Standard of Care in IVF
• Frozen Embryo Transfer (FET) versus “Fresh” ET: How to Make the Decision
• Frozen Embryo Transfer (FET): A Rational Approach to Hormonal Preparation and How new Methodology is Impacting IVF.
• Staggered IVF: An Excellent Option When. Advancing Age and Diminished Ovarian Reserve (DOR) Reduces IVF Success Rate
• Embryo Banking/Stockpiling: Slows the “Biological Clock” and offers a Selective Alternative to IVF-Egg Donation.
• Preimplantation Genetic Testing (PGS) in IVF: It Should be Used Selectively and NOT be Routine.
• Preimplantation Genetic Sampling (PGS) Using: Next Generation Gene Sequencing (NGS): Method of Choice.
• PGS in IVF: Are Some Chromosomally Abnormal Embryos Capable of Resulting in Normal Babies and Being Wrongly Discarded?
• PGS and Assessment of Egg/Embryo “competency”: How Method, Timing and Methodology Could Affect Reliability
• Treating Out-of-State and Out-of-Country Patients at Sher-IVF in Las Vegas:
• Traveling for IVF from Out of State/Country–
• A personalized, stepwise approach to IVF
• How Many Embryos should be transferred: A Critical Decision in IVF.
• The Role of Nutritional Supplements in Preparing for IVF
• Premature Luteinization (“the premature LH surge): Why it happens and how it can be prevented.
• IVF Egg Donation: A Comprehensive Overview

If you are interested in seeking my advice or services, I urge you to contact my concierge, Julie Dahan ASAP to set up a Skype or an in-person consultation with me. You can also contact Julie by phone or via email at 702-533-2691/ Julied@sherivf.com You can also apply online at http://www.SherIVF.com .

*FYI
The 4th edition of my newest book ,”In Vitro Fertilization, the ART of Making Babies” is available as a down-load through http://www.Amazon.com or from most bookstores and public libraries.

Geoffrey Sher MD

reply
Paige

Hi Dr. Sher, I’ve been a longtime reader.

I am only 28 and just did our second eound of IVF/PGS. My husband is in his late 30s. We have one living child conceived spontaneously with no issues and have had multiple unexplained losses since. We moved on to IVF/PGS since everything on my end was deemed normal. We then discovered my husband has a varicocele and high oxidative stress damaged sperm and high nomal DFI.

Between two cycles, I produced 10+ good eggs then “high quality” embryos that had any arresting after Day 3. Between two cycles, we had 6 blasts. We’re waiting on a mosaic report, but I’m desperate for my dreamed of son and was already undergoing FET protocol. Do you suspect any of these XYs could be mosaic?
XY +8 (graded AB)
XY +8 (graded BB)
XY -12, partial (graded BB)

I anxiously await hearing back from you. Thank you!

reply
Dr. Geoffrey Sher

When it comes to reproduction, humans are the poorest performers of all mammals. In fact we are so inefficient that up to 75% of fertilized eggs do not produce live births, and up to 30% of pregnancies end up being lost within 10 weeks of conception (in the first trimester). RPL is defined as two (2) or more failed pregnancies. Less than 5% of women will experience two (2) consecutive miscarriages, and only 1% experience three or more.
Pregnancy loss can be classified by the stage of pregnancy when the loss occurs:
• Early pregnancy loss (first trimester)
• Late pregnancy loss (after the first trimester)
• Occult “hidden” and not clinically recognized, (chemical) pregnancy loss (occurs prior to ultrasound confirmation of pregnancy)
• Early pregnancy losses usually occur sporadically (are not repetitive).
In more than 70% of cases the loss is due to embryo aneuploidy (where there are more or less than the normal quota of 46 chromosomes). Conversely, repeated losses (RPL), with isolated exceptions where the cause is structural (e.g., unbalanced translocations), are seldom attributable to numerical chromosomal abnormalities (aneuploidy). In fact, the vast majority of cases of RPL are attributable to non-chromosomal causes such as anatomical uterine abnormalities or Immunologic Implantation Dysfunction (IID).
Since most sporadic early pregnancy losses are induced by chromosomal factors and thus are non-repetitive, having had a single miscarriage the likelihood of a second one occurring is no greater than average. However, once having had two losses the chance of a third one occurring is double (35-40%) and after having had three losses the chance of a fourth miscarriage increases to about 60%. The reason for this is that the more miscarriages a woman has, the greater is the likelihood of this being due to a non-chromosomal (repetitive) cause such as IID. It follows that if numerical chromosomal analysis (karyotyping) of embryonic/fetal products derived from a miscarriage tests karyotypically normal, then by a process of elimination, there would be a strong likelihood of a miscarriage repeating in subsequent pregnancies and one would not have to wait for the disaster to recur before taking action. This is precisely why we strongly advocate that all miscarriage specimens be karyotyped.
There is however one caveat to be taken into consideration. That is that the laboratory performing the karyotyping might unwittingly be testing the mother’s cells rather than that of the conceptus. That is why it is not possible to confidently exclude aneuploidy in cases where karyotyping of products suggests a “chromosomally normal” (euploid) female.
Late pregnancy losses (occurring after completion of the 1st trimester/12th week) occur far less frequently (1%) than early pregnancy losses. They are most commonly due to anatomical abnormalities of the uterus and/or cervix. Weakness of the neck of the cervix rendering it able to act as an effective valve that retains the pregnancy (i.e., cervical incompetence) is in fact one of the commonest causes of late pregnancy loss. So also are developmental (congenital) abnormalities of the uterus (e.g., a uterine septum) and uterine fibroid tumors. In some cases intrauterine growth retardation, premature separation of the placenta (placental abruption), premature rupture of the membranes and premature labor can also causes of late pregnancy loss.
Much progress has been made in understanding the mechanisms involved in RPL. There are two broad categories:
1. Problems involving the uterine environment in which a normal embryo is prohibited from properly implanting and developing. Possible causes include:
• Inadequate thickening of the uterine lining
• Irregularity in the contour of the uterine cavity (polyps, fibroid tumors in the uterine wall, intra-uterine scarring and adenomyosis)
• Hormonal imbalances (progesterone deficiency or luteal phase defects). This most commonly results in occult RPL.
• Deficient blood flow to the uterine lining (thin uterine lining).
• Immunologic implantation dysfunction (IID). A major cause of RPL. Plays a role in 75% of cases where chromosomally normal preimplantation embryos fail to implant.
• Interference of blood supply to the developing conceptus can occur due to a hereditary clotting disorder known as Thrombophilia.
2. Genetic and/or structural chromosomal abnormality of the embryo.Genetic abnormalities are rare causes of RPL. Structural chromosomal abnormalities are slightly more common but are also occur infrequently (1%). These are referred to as unbalanced translocation and they result from part of one chromosome detaching and then fusing with another chromosome. Additionally, a number of studies suggest the existence of paternal (sperm derived) effect on human embryo quality and pregnancy outcome that are not reflected as a chromosomal abnormality. Damaged sperm DNA can have a negative impact on fetal development and present clinically as occult or early clinical miscarriage. The Sperm Chromatin Structure Assay (SCSA) which measures the same endpoints are newer and possibly improved methods for evaluating.

IMMUNOLOGIC IMPLANTATION DYSFUNCTION
Autoimmune IID: Here an immunologic reaction is produced by the individual to his/her body’s own cellular components. The most common antibodies that form in such situations are APA and antithyroid antibodies (ATA).
But it is only when specialized immune cells in the uterine lining, known as cytotoxic lymphocytes (CTL) and natural killer (NK) cells, become activated and start to release an excessive/disproportionate amount of TH-1 cytokines that attack the root system of the embryo, that implantation potential is jeopardized. Diagnosis of such activation requires highly specialized blood test for cytokine activity that can only be performed by a handful of reproductive immunology reference laboratories in the United States.
Alloimmune IID, i.e., where antibodies are formed against antigens derived from another member of the same species, is believed to be a relatively common immunologic cause of recurrent pregnancy loss.
Autoimmune IID is often genetically transmitted. Thus it should not be surprising to learn that it is more likely to exist in women who have a family (or personal) history of primary autoimmune diseases such as lupus erythematosus (LE), scleroderma or autoimmune hypothyroidism (Hashimoto’s disease), autoimmune hyperthyroidism (Grave’s disease), rheumatoid arthritis, etc. Reactionary (secondary) autoimmunity can occur in conjunction with any medical condition associated with widespread tissue damage. One such gynecologic condition is endometriosis. Since autoimmune IID is usually associated with activated NK and T-cells from the outset, it usually results in such very early destruction of the embryo’s root system that the patient does not even recognize that she is pregnant. Accordingly the condition usually presents as “unexplained infertility” or “unexplained IVF failure” rather than as a miscarriage.

Alloimmune IID, on the other hand, usually starts off presenting as unexplained miscarriages (often manifesting as RPL). Over time as NK/T cell activation builds and eventually becomes permanently established the patient often goes from RPL to “infertility” due to failed implantation. RPL is more commonly the consequence of alloimmune rather than autoimmune implantation dysfunction.
However, regardless, of whether miscarriage is due to autoimmune or alloimmune implantation dysfunction the final blow to the pregnancy is the result of activated NK cells and CTL in the uterine lining that damage the developing embryo’s “root system” (trophoblast) so that it can no longer sustain the growing conceptus. This having been said, it is important to note that autoimmune IID is readily amenable to reversal through timely, appropriately administered, selective immunotherapy, and alloimmune IID is not. It is much more difficult to treat successfully, even with the use of immunotherapy. In fact, in some cases the only solution will be to revert to selective immunotherapy plus using donor sperm (provided there is no “match” between the donor’s DQa profile and that of the female recipient) or alternatively to resort to gestational surrogacy.
DIAGNOSING THE CAUSE OF RPL
In the past, women who miscarried were not evaluated thoroughly until they had lost several pregnancies in a row. This was because sporadic miscarriages are most commonly the result of embryo numerical chromosomal irregularities (aneuploidy) and thus not treatable. However, a consecutive series of miscarriages points to a repetitive cause that is non-chromosomal and is potentially remediable. Since RPL is most commonly due to a uterine pathology or immunologic causes that are potentially treatable, it follows that early chromosomal evaluation of products of conception could point to a potentially treatable situation. Thus I strongly recommend that such testing be done in most cases of miscarriage. Doing so will avoid a great deal of unnecessary heartache for many patients.
Establishing the correct diagnosis is the first step toward determining effective treatment for couples with RPL. It results from a problem within the pregnancy itself or within the uterine environment where the pregnancy implants and grows. Diagnostic tests useful in identifying individuals at greater risk for a problem within the pregnancy itself include:

• Karyotyping (chromosome analysis) both prospective parents
• Assessment of the karyotype of products of conception derived from previous miscarriage specimens
• Ultrasound examination of the uterine cavity after sterile water is injected or sonohysterogram, fluid ultrasound, etc.)
• Hysterosalpingogram (dye X-ray test)
• Hysteroscopic evaluation of the uterine cavity
• Full hormonal evaluation (estrogen, progesterone, adrenal steroid hormones, thyroid hormones, FSH/LH, etc.)
• Immunologic testing to include:
a) Antiphospholipid antibody (APA) panel
b) Antinuclear antibody (ANA) panel
c) Antithyroid antibody panel (i.e., antithyroglobulin and antimicrosomal antibodies)
d) Reproductive immunophenotype
e) Natural killer cell activity (NKa) assay (i.e., K562 target cell test)
f) Alloimmune testing of both the male and female partners
TREATMENT OF RPL
Treatment for Anatomic Abnormalities of the Uterus: This involves restoration through removal of local lesions such as fibroids, scar tissue, and endometrial polyps or timely insertion of a cervical cerclage (a stitch placed around the neck of the weakened cervix) or the excision of a uterine septum when indicated.
Treatment of Thin Uterine Lining: A thin uterine lining has been shown to correlate with compromised pregnancy outcome. Often this will be associated with reduced blood flow to the endometrium. Such decreased blood flow to the uterus can be improved through treatment with sildenafil and possibly aspirin.
Sildenafil (Viagra) Therapy. Viagra has been used successfully to increase uterine blood flow. However, to be effective it must be administered starting as soon as the period stops up until the day of ovulation and it must be administered vaginally (not orally). Viagra in the form of vaginal suppositories given in the dosage of 25 mg four times a day has been shown to increase uterine blood flow as well as thickness of the uterine lining. To date, we have seen significant improvement of the thickness of the uterine lining in about 70% of women treated. Successful pregnancy resulted in 42% of women who responded to the Viagra. It should be remembered that most of these women had previously experienced repeated IVF failures.

Use of Aspirin: This is an anti-prostaglandin that improves blood flow to the endometrium. It is administered at a dosage of 81 mg orally, daily from the beginning of the cycle until ovulation.
Treating Immunologic Implantation Dysfunction with Selective Immunotherapy: Modalities such as IL/IVIg, heparinoids (Lovenox/Clexane), and corticosteroids (dexamethasone, prednisone, prednisolone) can be used in select cases depending on autoimmune or alloimmune dysfunction.
The Use of IVF in the Treatment of RPL
In the following circumstances, IVF is the preferred option:
1. When in addition to a history of RPL, another standard indication for IVF (e.g., tubal factor, endometriosis, and male factor infertility) is superimposed.
2. In cases where selective immunotherapy is needed to treat an immunologic implantation dysfunction.
The reason for IVF being a preferred approach in such cases is that in order to be effective, the immunotherapy needs to be initiated well before spontaneous or induced ovulation. Given the fact that the anticipated birthrate per cycle of COS with or without IUI is at best about 15%, it follows that short of IVF, to have even a reasonable chance of a live birth, most women with immunologic causes of RPL would need to undergo immunotherapy repeatedly, over consecutive cycles. Conversely, with IVF, the chance of a successful outcome in a single cycle of treatment is several times greater and, because of the attenuated and concentrated time period required for treatment, IVF is far safer and thus represents a more practicable alternative
Since embryo aneuploidy is a common cause of miscarriage, the use of preimplantation genetic diagnosis (PGD), with tests such as CGH, can provide a valuable diagnostic and therapeutic advantage in cases of RPL. PGD requires IVF to provide access to embryos for testing.
There are a few cases of intractable alloimmune dysfunction due to absolute DQ alpha matching where Gestational Surrogacy or use of donor sperm could represent the only viable recourse, other than abandoning treatment altogether and/or resorting to adoption. Other non-immunologic factors such as an intractably thin uterine lining or severe uterine pathology might also warrant that last resort consideration be given to gestational surrogacy.
The good news is that if a couple with RPL is open to all of the diagnostic and treatment options referred to above, a live birthrate of 70%–80% is ultimately achievable.

I strongly recommend that you visit http://www.DrGeoffreySherIVF.com. Then go to my Blog and access the “search bar”. Type in the titles of any/all of the articles listed below, one by one. “Click” and you will immediately be taken to those you select. Please also take the time to post any questions or comments with the full expectation that I will (as always) respond promptly.
• The IVF Journey: The importance of “Planning the Trip” Before Taking the Ride”
• Controlled Ovarian Stimulation (COS) for IVF: Selecting the ideal protocol
• IVF: Factors Affecting Egg/Embryo “competency” during Controlled Ovarian Stimulation(COS)
• The Fundamental Requirements For Achieving Optimal IVF Success
• Ovarian Stimulation for IVF using GnRH Antagonists: Comparing the Agonist/Antagonist Conversion Protocol.(A/ACP) With the “Conventional” Antagonist Approach
• Ovarian Stimulation in Women Who have Diminished Ovarian Reserve (DOR): Introducing the Agonist/Antagonist Conversion protocol
• Anti Mullerian Hormone (AMH) Measurement to Assess Ovarian Reserve and Design the Optimal Protocol for Controlled Ovarian Stimulation (COS) in IVF.
• Human Growth Hormone Administration in IVF: Does it Enhances Egg/Embryo Quality and Outcome?
• The BCP: Does Launching a Cycle of Controlled Ovarian Stimulation (COS). Coming off the BCP Compromise Response?
• Blastocyst Embryo Transfers Should be the Standard of Care in IVF
• IVF: How Many Attempts should be considered before Stopping?
• “Unexplained” Infertility: Often a matter of the Diagnosis Being Overlooked!
• IVF Failure and Implantation Dysfunction:
• The Role of Immunologic Implantation Dysfunction (IID) & Infertility (IID):PART 1-Background
• Immunologic Implantation Dysfunction (IID) & Infertility (IID):PART 2- Making a Diagnosis
• Immunologic Dysfunction (IID) & Infertility (IID):PART 3-Treatment
• Thyroid autoantibodies and Immunologic Implantation Dysfunction (IID)
• Immunologic Implantation Dysfunction: Importance of Meticulous Evaluation and Strategic Management:(Case Report
• Intralipid and IVIG therapy: Understanding the Basis for its use in the Treatment of Immunologic Implantation Dysfunction (IID)
• Intralipid (IL) Administration in IVF: It’s Composition; How it Works; Administration; Side-effects; Reactions and Precautions
• Natural Killer Cell Activation (NKa) and Immunologic Implantation Dysfunction in IVF: The Controversy!
• Endometrial Thickness, Uterine Pathology and Immunologic Factors
• Vaginally Administered Viagra is Often a Highly Effective Treatment to Help Thicken a Thin Uterine Lining
• Treating Out-of-State and Out-of-Country Patients at Sher-IVF in Las Vegas:
• A personalized, stepwise approach to IVF
• How Many Embryos should be transferred: A Critical Decision in IVF.
• The Role of Nutritional Supplements in Preparing for IVF

If you are interested in seeking my advice or services, I urge you to contact my concierge, Julie Dahan ASAP to set up a Skype or an in-person consultation with me. You can also contact Julie by phone or via email at 702-533-2691/ Julied@sherivf.com You can also apply online at http://www.SherIVF.com .

*FYI
The 4th edition of my newest book ,”In Vitro Fertilization, the ART of Making Babies” is available as a down-load through http://www.Amazon.com or from most bookstores and public libraries.

Geoffrey Sher MD

reply
Paige

Hi Dr. Sher,

I really appreciate your in depth response, bu I was hoping you could answer my question. We did all of that testing and more, hence why IVF with PGS was our last resort and two cycles let us know that my husband’s sperm is likely the culprit. We were planning to do an immune protocol before FET just in case, though the abundance of abnormals for a 28 year old with no conditions, no abnormal tests and an older husband wih high OSA sperm seems like it has been unviability at work.

Do you think any of these blasts could be mosaic and worth transferring, since you noted to other people which blasts might hold surprise for them?
XY Trisomy 8 (AB)
XY Trisomy 8 (BB)
XY Partial deletion 12 (BB)

reply
Colleen

Hi Dr. Sher.
I am 39 and after two egg retrieval’s all I have are two PGS abnormal embryos. I have good ovarian reserve but apparently poor egg quality. My physician has encouraged me to pursue using an egg donor. I’m not ready yet. I had 8 mature eggs, 7 fertilized and only one went to blast the first round. Second round, 12 mature eggs, 10 fertilized and only one went to blast. What protocol would you recommend for egg quality?
I’m very curious about the PGS results..
do you recommend retesting?
Embryo #1. 47, XY +20
Embryo #2. 44, XX -1,-9
Would you consider transferring either of those?
Any advice is welcome!! Thank you!

reply
Dr. Geoffrey Sher

I would probably transfer embryo #1 as a possible mosaic.

The potential for a woman’s eggs to undergo orderly development and maturation, while in large part being genetically determined can be profoundly influenced by the woman’s age, her “ovarian reserve” and proximity to menopause. It is also influenced by the protocol used for controlled ovarian stimulation (COH) which by fashioning the intra-ovarian hormonal environment, profoundly impacts egg development and maturation.
After the menarche (age at which menstruation starts) a monthly process of repeatedly processing eggs continues until the menopause, by which time most eggs will have been used up, and ovulation and menstruation cease. When the number of eggs remaining in the ovaries falls below a certain threshold, ovarian function starts to wane over a 5 to10-years. This time period is referred to as the climacteric. With the onset of the climacteric, blood Follicle Stimulating Hormone (FSH) and later also Luteinizing Hormone (LH) levels begin to rise…. at first slowly and then more rapidly, ultimately culminating in the complete cessation of ovulation and menstruation (i.e. menopause).

One of the early indications that the woman has entered the climacteric and that ovarian reserve is diminishing DOR) , is the detection of a basal blood FSH level above 9.0 MIU/ml and/ or an AMH level og <2.0ng/ml.
Prior to the changes that immediately precede ovulation, virtually all human eggs have 23 pairs (i.e. 46) of chromosomes. Thirty six to forty hours prior to ovulation, a surge occurs in the release of LH by the pituitary gland. One of the main e purposes of this LH surge is to cause the chromosomes in the egg to divide n half (to 23 in number) in order that once fertilized by a mature sperm ends up having 23 chromosomes) the resulting embryo will be back to having 46 chromosomes. A “competent” mature egg is one that has precisely 23 chromosomes, not any more or any less. It is largely the egg, rather than the sperm that determines the chromosomal integrity of the embryo and only an embryo that has a normal component of 46 chromosomes (i.e. euploid) is “competent” to develop into a healthy baby. If for any reason the final number of chromosomes in the egg is less or more than 23 (aneuploid), it will be incapable of propagating a euploid, “competent” embryo. Thus egg/embryo aneuploidy (“incompetence”) is the leading cause of human reproductive dysfunction which can manifest as: arrested embryo development and/or failed implantation (which often presents as infertility), early miscarriage or chromosomal birth defects (e.g. Down’s syndrome). While most aneuploid (“incompetent”) embryos often fail to produce a pregnancy, some do. However, most such pregnancies miscarry early on. On relatively rare occasions, depending on the chromosome pair involved, aneuploid embryos can develop into chromosomally defective babies (e.g. Down’s syndrome).

Up until a woman reaches her mid- thirties, at best, 1:2 of her eggs will likely be chromosomally normal. As she ages beyond her mid-thirties there will be a a progressive decline in egg quality such that by age 40 years only about 15%-20% of eggs are euploid and, by the time the woman reaches her mid-forties, less than 10% of her eggs are likely to be chromosomally normal. While most aneuploid embryos do appear to be microscopically abnormal under the light microscope, this is not invariably so. In fact, many aneuploid embryos a have a perfectly normal appearance under the microscope. This is why it is not possible to reliably differentiate between competent and incompetent embryos on the basis of their microscopic appearance (morphologic grade) alone.

The process of natural selection usually precludes most aneuploid embryos from attaching to the uterine lining. Those that do attach usually do so for such only a brief period of time. In such cases the woman often will not even experience a postponement of menstruation. There will be a transient rise in blood hCG levels but in most cases the woman will be unaware of even having conceived (i.e. a “chemical pregnancy”). Alternatively, an aneuploid embryo might attach for a period of a few weeks before being expelled (i.e. a “miscarriage”). Sometimes (fortunately rarely) an aneuploid embryo will develop into a viable baby that is born with a chromosomal birth defect (e.g. Down’s syndrome).
The fact that the incidence of embryo aneuploidy invariably increases with advancing age serves to explain why reproductive failure (“infertility”, miscarriages and birth defects), also increases as women get older.

It is an over-simplification to represent that diminishing ovarian reserve as evidenced by raised FSH blood levels (and other tests) and reduced response to stimulation with fertility drugs is a direct cause of “poor egg/ embryo quality”. This common misconception stems from the fact that poor embryo quality (“incompetence”) often occurs in women who at the same time, because of the advent of the climacteric also have elevated basal blood FSH/LH levels and reduced AMH. But it is not the elevation in FSH or the low AMH that causes embryo “incompetence”. Rather it is the effect of advancing age (the “biological clock”) resulting a progressive increase in the incidence of egg aneuploidy, which is responsible for declining egg quality. Simply stated, as women get older “wear and tear” on their eggs increases the likelihood of egg and thus embryo aneuploidy. It just so happens that the two precipitating factors often go hand in hand.

The importance of the IVF stimulation protocol on egg/embryo quality cannot be overstated. This factor seems often to be overlooked or discounted by those IVF practitioners who use a “one-size-fits-all” approach to ovarian stimulation. My experience is that the use of individualized/customized COS protocols can greatly improve IVF outcome in patients at risk – particularly those with diminished ovarian reserve (“poor responders”) and those who are “high responders” (women with PCOS , those with dysfunctional or absent ovulation, and young women under 25 years of age).
While no one can influence underlying genetics or turn back the clock on a woman’s age, any competent IVF specialist should be able to tailor the protocol for COS to meet the individual needs of the patient.
During the normal ovulation cycle, ovarian hormonal changes are regulated to avoid irregularities in production and interaction that could adversely influence follicle development and egg quality. As an example, small amounts of androgens (male hormones such as testosterone) that are produced by the ovarian stroma (the tissue surrounding ovarian follicles) during the pre-ovulatory phase of the cycle enhance late follicle development, estrogen production by the granulosa cells (cells that line the inner walls of follicles), and egg maturation.
However, over-production of testosterone can adversely influence the same processes. It follows that protocols for controlled ovarian stimulation (COS should be geared toward optimizing follicle growth and development (without placing the woman at risk from overstimulation), while at the same time avoiding excessive ovarian androgen production. Achievement of such objectives requires a very individualized approach to choosing the protocol for COS with fertility drugs as well as the precise timing of the “trigger shot” of hCG.

It is important to recognize that the pituitary gonadotropins, LH and FSH, while both playing a pivotal role in follicle development, have different primary sites of action in the ovary. The action of FSH is mainly directed towards the cells lining the inside of the follicle that are responsible for estrogen production. LH, on the other hand, acts primarily on the ovarian stroma to produce male hormones/ androgens (e.g. androstenedione and testosterone). A small amount of testosterone is necessary for optimal estrogen production. Over-production of such androgens can have a deleterious effect on granulosa cell activity, follicle growth/development, egg maturation, fertilization potential and subsequent embryo quality. Furthermore, excessive ovarian androgens can also compromise estrogen-induced endometrial growth and development.

In conditions such as polycystic ovarian syndrome (PCOS), which is characterized by increased blood LH levels, there is also increased ovarian androgen production. It is therefore not surprising that “poor egg/embryo quality” is often a feature of this condition. The use of LH-containing preparations such as Menopur further aggravates this effect. Thus we recommend using FSH-dominant products such as Follistim, Puregon, and Gonal-F in such cases. While it would seem prudent to limit LH exposure in all cases of COS, this appears to be more vital in older women, who tend to be more sensitive to LH

It is common practice to administer gonadotropin releasing hormone agonists (GnRHa) agonists such as Lupron, and, GnRH-antagonists such as Ganirelix and Orgalutron to prevent the release of LH during COS. GnRH agonists exert their LH-lowering effect over a number of days. They act by causing an initial outpouring followed by a depletion of pituitary gonadotropins. This results in the LH level falling to low concentrations, within 4-7 days, thereby establishing a relatively “LH-free environment”. GnRH Antagonists, on the other hand, act very rapidly (within a few hours) to block pituitary LH release, so as achieve the same effect.

Long Agonist (Lupron/Buserelin) Protocols: The most commonly prescribed protocol for Lupron/gonadotropin administration is the so-called “long protocol”. Here, Lupron is given, starting a week or so prior to menstruation. This results in an initial rise in FSH and LH level, which is rapidly followed by a precipitous fall to near zero. It is followed by uterine withdrawal bleeding (menstruation), whereupon gonadotropin treatment is initiated while daily Lupron injections continue, to ensure a “low LH” environment. A modification to the long protocol which I prefer using in cases of DOR, is the Agonist/Antagonist Conversion Protocol (A/ACP) where, upon the onset of a Lupron-induced bleed , this agonist is supplanted by an antagonist (Ganirelix/Cetrotide/Orgalutron) and this is continued until the hCG trigger. In many such cases I supplement with human growth hormone (HGH) to try and further enhance response and egg development.

Lupron Flare/Micro-Flare Protocol: Another approach to COS is by way of so-called “(micro) flare protocols”. This involves initiating gonadotropin therapy simultaneous with the administration of GnRH agonist (e.g. Lupron/Buserelin). The intent here is to deliberately allow Lupron to elicit an initial surge (“flare”) in pituitary FSH release in order to augment FSH administration by increased FSH production. Unfortunately, this “spring board effect” represents “a double edged sword” because while it indeed increases the release of FSH, it at the same time causes a surge in LH release. The latter can evoke excessive ovarian stromal androgen production which could potentially compromise egg quality, especially in older women and women with PCOS, whose ovaries have increased sensitivity to LH. I am of the opinion that by evoking an exaggerated ovarian androgen response, such “(micro) flare protocols” can harm egg/embryo quality and reduce IVF success rates, especially in older women, and in women with diminished ovarian reserve. Accordingly, I do not prescribe them at all.

Estrogen Priming – My approach for “Poor Responders” Our patients who have demonstrated reduced ovarian response to COS as well as those who by way of significantly raised FSH blood levels are likely to be “poor responders”, are treated using a “modified” long protocol. The approach involves the initial administration of GnRH agonist for a number of days to cause pituitary down-regulation. Upon menstruation and confirmation by ultrasound and measurement of blood estradiol levels that adequate ovarian suppression has been achieved, the dosage of GnRH agonist is drastically lowered and the woman is given twice-weekly injections of estradiol for a period of 8. COS is thereupon initiated using a relatively high dosage of FSH-(Follistim, Bravelle, Puregon or Gonal F) which is continued along with daily administration of GnRH agonist until the “hCG trigger.” By this approach we have been able to significantly improve ovarian response to gonadotropins in many of hitherto “resistant patients”.
The “Trigger”: hCG (Profasi/Pregnyl/Novarel) versus Lupron: With ovulation induction using fertility drugs, the administration of 10,000U hCGu (the hCG “trigger”) mimics the LH surge, sending the eggs (which up to that point are immature (M1) and have 46 chromosomes) into maturational division (meiosis) This process is designed to halve the chromosome number , resulting in mature eggs (M2) that will have 23 chromosomes rather that the 46 chromosomes it had prior to the “trigger”. Such a chromosomally normal, M2 egg, upon being fertilized by mature sperm (that following maturational division also has 23 chromosomes) will hopefully propagate embryos that have 46 chromosomes and will be “:competent” to propagate viable pregnancies. The key is to trigger with no less than 10,000U of hCGu (Profasi/Novarel/Pregnyl) and if hCGr (Ovidrel) is used, to make sure that 500mcg (rather than 250mcg) is administered. In my opinion, any lesser dosage will reduce the efficiency of meiosis, and increase the risk of the eggs being chromosomally abnormal. . I also do not use the agonist (Lupron) “trigger”. This approach which is often recommended for women at risk of overstimulation, is intended to reduce the risk of OHSS. The reason for using the Lupron trigger is that by inducing a surge in the release of LH by the pituitary gland it reduces the risk of OHSS. This is true, but this comes at the expense of egg quality because the extent of the induced LH surge varies and if too little LH is released, meiosis can be compromised, thereby increasing the percentage of chromosomally abnormal and of immature (M1) eggs. The use of “coasting” in such cases (see below) can obviate this effect.

Severe Ovarian Hyperstimulation Syndrome (OHSS): Women with certain types of absent or dysfunctional ovulation as well as those who have polycystic ovarian syndrome (PCOS) are highly sensitive to gonadotropins and are at risk of developing OHSS. Such women are also more likely than others to produce poor quality eggs/embryos which, they are often led to believe is attributable to an intrinsic egg defect that is characteristic of their PCOS condition. This is not necessarily so. The most likely reason as to why many women with PCOS develop an excessive number of follicles and then go on to produce poor quality eggs/embryos has to do with the fact that, in an attempt to contain reduce the risk of OHSS they are often administered hCG prematurely – prior to the attainment of optimal egg maturation.

“Prolonged Coasting”: In the early nineties, we introduced “Prolonged Coasting”, a procedure which eliminates the risk of OHSS while allowing the hCG trigger to be deferred for long enough as to allow for optimal follicle/egg maturation to take place. Coasting involves withholding gonadotropin therapy while the administration of GnRH agonist/antagonist is continued. The daily measurement of blood estradiol is continued until the concentration drops below a safe threshold level, at which time HCG is administered (regardless of the number of follicles). When appropriately implemented “coasting” results in the production of good quality eggs/embryos, in circumstances where this might otherwise not have been possible.

If you are interested in my advice or medical services, I urge you to contact my concierge, Julie Dahan ASAP to set up a Skype or an in-person consultation with me. You can also contact Julie by phone or via email at 702-533-2691/ Julied@sherivf.com. You can also apply online at http://www.SherIVF.com.
Also, my book, “In Vitro Fertilization, the ART of Making Babies” is available as a down-load through http://www.Amazon.com or from most bookstores and public libraries.

Geoffrey Sher MD

reply
Rachel

Would love your thoughts! I am 39 and just completed my 2nd IVF cycle. The first round was 6 months ago, where we ended up with 3 abnormal embryos 48/+14/+15/+21/-22 , 45/-13 and 46/dup(6)(q22q27). My doctor said the first one (48/+14/+15/+21/-22) would be the only one he would be willing to transfer since it was mosaic. We decided to pass and just completed another round (lupron flare this time) where we are waiting on results from 2 day-5 blastocysts. I am of course hoping for better results this time but I cant help to wonder about our mosaic from round 1.

reply
Dr. Geoffrey Sher

Very respectfully Rachel, I disagree with your Doctor. There is no way to know with cofidence whether an embryo is “mosaic”. However, the ones that are most likely to be so are the ones with autosomal single chromosome defects. So in your case, I think #2 with a -13 monosomy is the best to try and #3 possibly also.

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

reply
Nadege Montagnon

Dear Doctor,
I am 41 years old.
We did 2 rounds of IVF, each time with PGS.
3 blastocysts were tested.
The PGS results were the following:
– Abnormal: +7, +21
– Abnormal: -13
-Abnormal: -19
Do you think that these embryos have a chance to be mosaic and would have the possibility to autocorrect themselves? Would you do a transfer of such embryos?
Our doctor told us that they were abnormal and that there would not be any transfer.
Thank you in advance for your response.
Ps: sorry for my English, but I am French.

reply
Dr. Geoffrey Sher

Yes! The -13 and -19 could be mosaic.

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or preimplantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe PhD were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no practical test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of aneuploid embryos to the uterus.
Certain meiotic aneuploid trisomy embryos (e.g. trisomies 13, 18, & 21) can and sometimes do, result in aneuploid concepti. Thus, in my opinion, unless the woman/couple receiving such embryos is willing to commit to terminating a resulting pregnancy found through amniocentesis or chorionic villus sampling (CVS) to be so affected, she/they are probably best advised not to transfer such embryos. Other autosomal trisomy embryos will hardly ever produce viable euploid concepti and can thus, in my opinion be transferred in the hope that auto correction will occur in-utero. However, in all cases, and amniocentesis or CVS should be performed to make certain that the baby is euploid. Conversely, no autosomal monosomy embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomal monosomy embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated in any such cases, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing (amniocentesis/CVS) aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

reply
Justyna Akyondem

Dr. Sher:

Thank you so much for posting this video and article. This is incredibly helpful!

Are there specific questions that I would need to ask my lab in order to get a good report of the PGS results? I have found that detailed information is given only when asked for.

Also what are your thoughts about the accuracy of a single 6-10 cell Trophoderm biopsy on a day 5 blastocyst. I have read a number of papers suggesting that such a small biopsy sample size is not adequate to accurately identify the existence of multiple cell lines in a day 5 blastocyst.

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Dr. Geoffrey Sher

Just asked for a comprehensive report…That should do it. I think the 6-10 cell biopsy is adequate.

Geoff Sher

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Chrissy

What are you thoughts on transferring a monosomy 20 embryo? The first time it was tested it came back as “no result” so the clinic did a re-biopsy and sent back in and it came back with the above abnormality. Would you say it’s likely too abnormal?

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Dr. Geoffrey Sher

I would do the transfer. It could be a mosaic.

Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or pre-implantation embryo development, and represents a major cause of early pregnancy loss. About a decade ago, I and an associate, Levent Keskintepe Ph.D were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3 fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Most IVF programs that offer PGS services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, there is now growing evidence to suggest that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrection”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases occurring within our IVF network. So clearly , summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring.
Thus by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.” As stated, some mosaic embryos will In the process of subsequent cell replication convert to the normal euploid state (i.e. autocorrect)
It is against this background, that an ever increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1. Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2. “Mitotic aneuploidy” occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically euploid early embryo mutate and become aneuploid. This is referred to as mosaicism. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to differentiate between these two varieties of aneuploidy would be of considerable clinical value. And would provide a strong argument in favor of preserving certain aneuploid embryos for future dispensation.
Aneuploidy, involves the addition (trisomy) or subtraction (monosomy) of one chromosome in a given pair. As previously stated, some aneuploidies are meiotic in origin while others are mitotic “mosaics”. Certain aneuploidies involve only a single, chromosome pair (simple aneuploidy) while others involve more than a single pair (i.e. complex aneuploidy). Aside from monosomy involving absence of the y-sex chromosome (i.e. XO) which can resulting in a live birth (Turner syndrome) all monosomies involving autosomes (non-sex chromosomes) are lethal and will not result in viable offspring). Some autosomal meiotic aneuploidies, especially trisomies 13, 18, 21, can progress to viable, but severely chromosomally defective babies. All other meiotic autosomal trisomies will almost invariably, either not attach to the uterine lining or upon attachment, will soon be rejected. All forms of meiotic aneuploidy are irreversible while mitotic aneuploidy (“mosaicism) often autocorrects in the uterus. Most complex aneuploidies are meiotic in origin and will almost invariably fail to propagate viable pregnancies.
There is presently no microscopic or genetic test that can reliable differentiate between meiotic and mitotic aneuploidy. Notwithstanding this, the fact that some “mosaic” embryos can autocorrect in the uterus, makes a strong argument in favor of transferring aneuploid of embryos in the hope that the one(s) transferred might be “mosaic” and might propagate viable healthy pregnancies. On the other hand, it is the fear that embryo aneuploidy might result in a chromosomally abnormal baby that has led many IVF physicians to strongly oppose the transfer of any aneuploid embryos to the uterus.
While certain meiotic aneuploid trisomies (e.g. trisomies 13, 18, & 21) can and sometimes do result in chromosomally defective babies, no other meiotic autosomal trisomies can do so. Thus the transfer of trisomic embryos in the hope that one or more might be mosaic, should exclude the use of embryos with trisomies 13, 18 or 21. Conversely, no autosomal monosomic embryos are believed to be capable of resulting in viable pregnancies, thereby making the transfer of autosomally monosomic embryos, in the hope that they are “mosaic”, a far less risky proposition. Needless to say, if such action is being contemplated, it is absolutely essential to make full disclosure to the patient (s) , and to insure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed.

Geoff Sher

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Brianna

What are your thoughts/opinions on transferring an XXY or an XYY embryo? Thanks!

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