Men with no sperm in their ejaculates (azoospermia), whether due to non-obstructive or obstructive (usually post-vasectomy) causes, can have their sperm accessed surgically and still propagate pregnancies. There are 2 methods by which this can be achieved. : 1) TESE (testicular sperm extraction), where a biopsy of the testis is done or, 2) TESA (testicular sperm aspiration), which involves introducing a needle into the testis and aspirating fluid and tissue. Both methods can be conducted under local anesthesia and both will provide sperm-containing tissue and fluid for immediate processing and fertilization (using ICSI) or cryostorage for future use. However, the question is: Which method yields better results. An Israeli study performed on men with non-obstructive azoospermia, conducted about a decade ago, compared the results of TESE with those from TESA in the same patients and found TESE to be the preferred approach.
TSE/TESA is the preferred method for accessing sperm in men with azoospermia. By far the commonest indication for using this approach is post-vasectomy obstructive azoospermia where the use of TESE/TESA is far more successful and uncomplicated than is the alternative of having the man undergo surgical reversal. In fact, TESE/TESA yields a comparable IVF birth rate as for controls where normal sperm derived through masturbation is used. The approach is simple, relatively low-cost, and safe. In most cases, it is relatively painless and has a low complication rate. Moreover, in post-vasectomy men, it avoids the need for riskier and painful surgery designed to reconnect sperm ducts (vasa deferentia) while enabling the man to retain his chosen method of contraception after having propagated another pregnancy. In addition surgical vasectomy often fails to successfully reestablished duct patency and even when successful it often results in the subsequent reocclusion of the sperm ducts due to scar tissue formation. Moreover, in a large percentage of cases where vasectomy reversal was performed > 5 years after the vasectomy antisperm antibodies develop and this will almost always preclude subsequent natural conception even in cases where surgery had reestablished duct patency.
While in some cases of non-obstructive azoospermia, TESA/TESE will yield sperm capable of achieving fertilization through ICSI and also subsequent viable pregnancies, success rates are low. However, in such cases, this approach yields the only possibility of the male partner participating genetically in propagating pregnancy.