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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 (Schlegel at el.) 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 (Schlegel et al. NYH-Cornell)

Date of MESA Procedure8/93 - 2/953/95 - 4/98
Fertilization Rate172/336 (51%)744/918 (81%)
Clinic Pregnancy Rate17/37 (46%)62/81 (76%)
Ongoing/Delivered15/37 (41%)53/81 (65%)

To summarize:

  1. 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. 

  2. 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. 

  3. 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.

Suggested References

1. Schlegel PN, Berkeley AS, Goldstein M, Cohen J, et al. Epididymal micropuncture with in vitro fertilization and oocyte micromanipulation for the treatment of unreconstructable obstructive azoospermia. Fertil Steril 61(5):895-901, 1994.

2. . Schlegel PN, Palermo GD, Alikani M, et al. Micropuncture retrieval of epididymal sperm with in vitro fertilization: importance of in vitro micromanipulation techniques. Urology 46:238-241, 1995.

3. Schlegel PN,Palermo GD, Goldstein M, Menendez S, Zaninovic N, Veeck LL, Rosenwaks Z: Testicular sperm extraction with ICSI for non-obstructive azoospermia. Urology, 49:435-440,1997

4. Schlegle PN, Girardi SK: Clinical review: In vitro fertilization for male factor infertility. J Clin Endocrinol Metab, 82:709-719, 1997

5. Craft IL, Khalifa Y, Boulos A, et al. Factors influencing the outcome of in-vitro fertilization with percutaneous aspirated epididymal spermatozoa and intracytoplasmic sperm injection in azoospermic men. Hum Reprod 10:1791-1794, 1995.

6. Harari O, Bourne H, McDonald M, et al. Intracytoplasmic sperm injection: a major advance in the management of severe male subfertility. Fertil Steril 64: 360-368. 1995

7. Oates RD and Amos JA. The genetic basis of congenital bilateral absence of the vas deferens and cystic fibrosis. J Androl 15:1-8, 1994.

8. Schlegel PN. Sperm retrieval and in-vitro fertilization. Curr Opin Urol 4:328-332, 1994.

9. Silber SJ, Ord T, Balmaceda J, et al. Congenital absence of the vas deferens: the fertilizing capacity of human epididymal sperm. N Engl J Med 323: 1788-1792, 1990.

10. Silber SJ, Nagy ZP, Liu J, et al. Conventional in-vitro fertilization versus intracytoplasmic sperm injection for patients requiring microsurgical sperm aspiration.Hum Reprod 9:1705-1709, 1994.

11. Silber SJ, Van Steirteghem AC, Liu J, et al. High fertilization and pregnancy rate after intracytoplasmic sperm injection with spermatozoa obtained from testicle biopsy. Hum Reprod 10:148-152, 1995.

12. The sperm microaspiration retrieval techniques study group. Results in the United States with microaspiration retrieval techniques and assisted reproductive technologies. J Urol 151:1255-1259, 1994. 

13. Kahraman S, Ozgur S, Altas C, et al: Fertility with testicular sperm extraction and intracytoplasmic sperm injection in non-obstructive azoospermic men. Hum Reprod 11(4):756-760,1994

Center for Male Reproductive Medicine & Microsurgery Weill Cornell Medicine
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New York, NY 10065