The superior success rates with MESA and IVF/ICSI can be ascribed to several factors. First, the experience of the centers performing IVF/ICSI plays a large role. The centers that have had the greatest experience with MESA and IVF/ICSI also have demonstrated consistently outstanding results for IVF/ICSI using ejaculated sperm. By direct injection of sperm into the oocyte cytoplasm, ICSI has allowed for even severely abnormal ejaculated sperm to fertilize and achieve pregnancy. Secondly, the microsurgical technique is very important to the success of MESA. Microsurgical epididymal sperm aspiration allows for meticulous hemostasis during retrieval and therefore minimal contamination of epididymal fluid with blood cells. In addition, microsurgical aspiration allows for more than adequate amounts of sperm to be retrieved per aspiration procedure so that in addition to processing a portion immediately, sperm may be preserved for later cycles limiting the patient to one procedure for sperm retrieval.
Experience with the last 81 couples with obstructive azoospermia who selected to undergo MESA-ICSI at our institution from March, 1995 to April, 1998 at Cornell is presented. Sperm was retrieved from the epididymis in 81/81 (100%) attempts, despite multiple aliquots of previous unsuccessful sperm retrieval attempts at other institutions. In all 81 cases motile sperm were cryopreserved as well. Clinical pregnancies were achieved in 76%(62/81) cycles for these couples. Ongoing pregnancies or deliveries have occurred for in 65% (53/81) cycles of simultaneous MESA-ICSI.
Simultaneous MESA-ICSI appears to provide optimal pregnancy and delivery rates for couples where the man has unreconstructable reproductive tract obstruction
MESA-ICSI: Obstructive Azoospermia
Date of MESA Procedure | 8/93 - 2/95 | 3/95 - 4/98 |
Cycles | 37 | 81 |
Fertilization Rate | 172/336 (51%) | 744/918 (81%) |
Clinic Pregnancy Rate | 17/37 (46%) | 62/81 (76%) |
Ongoing/Delivered | 15/37 (41%) | 53/81 (65%) |
To summarize:
- The location of optimal sperm quality in obstructed men differs from unobstructed men in that motile sperm capable of fertilization can be retrieved from the more proximal portions of the epididymis, and efferent ducts, whereas the distal obstructed reproductive tract is the site of sperm degeneration.
- The micropuncture technique of epididymal sperm aspiration has the advantages of minimal contamination by blood cells, meticulous hemostasis, and the ability to retrieve ample amounts of fluid for immediate use and for cryopreservation.
- Of the sperm retrieval and assisted reproductive techniques, the most successful combination reported to date is microsurgical epididymal aspiration with intracytoplasmic sperm injection. Ongoing pregnancy and delivery rates of 48 percent or more per attempt at sperm and egg retrieval are currently achieved at experienced centers.