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NEW HOPE FOR AZOOSPERMIC MENRupin Shah
Consultant Andrologist and Microsurgeon, Bhatia GeneralHospital, Mumbai 400 007.
For most couples trying to have a child, the finding of azoospermia - the absence of sperm in the semen - comes as a traumatic shock. In the past, little could be offered to these couples. With the exception of a few men in whom surgical bypass of an obstruction was successful, the only options these couples had was donor insemination or adoption. Now, with the availability of microsurgical operative techniques and the development of intracytoplasmic sperm injection, most men with azoospermia can look forward to fathering a child. This review provides a brief introduction to the various therapeutic options available for the treatment of an azoospermic man.
Intra Cytoplasmic Sperm Injection (ICSI)
ICSI has revolutionized male infertility management in the 90’s. It is a method of achieving in vitro fertilization by the direct injection of a single sperm into an oocyte. Since ICSI bypasses many of the natural barriers to fertilization, even sperm that are normally incapable of fertilization can achieve fertilization and pregnancy when used for ICSI. Only as many sperm are required as there are oocytes; hence, pregnancy is possible even when there are only very few sperms. Thus, a few immature sperm aspirated from the testis or epididymis are enough for successful ICSI. This has dramatically changed the treatment options in men with azoospermia.
Obstructive azoospermia
These men have normal sperm production in their testes, but there are no sperm in the semen due to an obstruction in the spermatic pathway.
Epididymal and vasal blocks : The older, macrosurgical technique of bypassing these blocks by vaso-epididymal anastomosis (VEA) and vaso-vasal anastomosis (VVA) was successful only in a small proportion of cases since the epididymis and vas are too small to be properly operated upon without magnification. With the advent of the operating microscope and the development of microsurgical techniques of VEA and VVA, the success of these procedures has increased significantly with pregnancy rates of 30% (for VEA) to 70% (for VVA). If the microsurgery fails, or if the couple wants a quicker pregnancy, then sperm can be aspirated from the epididymis with a simple needle and used for ICSI with a pregnancy rate of 25% to 40% per cycle.
Vas aplasia : 10 per cent of men with obstructive azoospermia are born with bilateral absence of the vasa deferentia. No reconstructive surgery is possible in these cases. The creation of a spermatocele to collect sperm for aspiration was attempted in the past but was given up because of very low success rates. Hence, until recently no effective therapy was available for these men. Now, with the development of ICSI, pregnancy can be achieved for aspirating sperm from the epididymis of these men and using the sperm for ICSI.
Testicular failure
While men with obstructive azoospermia could occasionally be helped by surgery, for men with non-obstructive azoospermia there used to be no possibility at all of fathering a child with their own sperm. Now, ICSI offers hope to some of these desperate men. Around 30% of men with testicular failure will have a few areas of sperm production scattered through their testes. These sperm are too few to travel the epididymis and appear in the semen, but can be directly retrieved from the testis by doing multiple micro-biopsies. These scanty, barely motile sperm are sufficient for ICSI and result in pregnancy rates of around 20% per attempt.
For those men in whom absolutely no sperm are found, the only options are still donor insemination or adoption. However, researchers are already trying to mature sperm in the laboratory and soon it may become possible to take sperm precursor cells from the testis and use them to achieve a viable pregnancy.
CONCLUSION
Most men with azoospermia will have a few sperm in their epididymis or testis. Some can be helped by reconstructive surgery; in the remaining, pregnancy can be achieved through the procedure of ICSI. The only limiting factor, in our country, is the unavoidable high cost of ICSI.
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