USE OF EPIDIDYMAL SPERM FOR ASSISTED REPRODUCTION IN MEN WITH ACQUIRED, IRREPARABLE OBSTRUCTIVE AZOOSPERMIA

Microsurgical epididymal sperm aspiration (MESA) and in vitro fertiliz ation (IVF) is primarily offered to men with congenital absence of the vas deferens (CAVD). However, the IVF capacity of these epididymal sp erm is low (<15%) and unpredictable. In this study, IVF and intracytop lasmic sperm injection (ICSI) results in patients with non-congenital, irreparable obstructive azoospermia were analysed. Thirty-three patie nts were evaluated for a total of 37 cycles of MESA and IVE. Most had obstruction secondary to failed vasectomy reversal and to epididymal b lockage. The overall fertilization rate was 30% with regular IVF and 2 6% with ICSI, and six clinical pregnancies were obtained. Both rates a re significantly higher than the IVF rate previously reported with spe rm from men with CAVD (13%, P<0.00001). In men with non-congenital obs tructive azoospermia, a significant difference was found in the averag e sperm count (56.9x10(6) v. 12.3x10(6), P<0.04) and total motile coun t (16.6x10(6) v. 1.6x10(6), P<0.01) respectively for patients who achi eved IVF and those who did not. It is concluded that (a) the real IVF capacity of human epididymal sperm is 30%, or 42%, if calculated only for patients who achieved fertilization, (b) this higher rate is an in direct support of the hypothesis that sperm from men with CAVD have in trinsic biochemical defects, related to cystic fibrosis mutations, res ponsible for their low and unpredictable IVF rate, and (c) MESA and IV F can be offered at the same time or as an alternative to patients req uesting vasectomy reversal.