Received September 13, 2001
Accepted October 09, 2001

The aim of this study was to analyze the outcome of ICSI cycles in infertile couples in which the main diagnosis of infertility was azoospermia of obstructive and non-obstructive origin. Significantly lower fertilization rate (64% vs. 73%, p=0.02), clinical pregnancy rate (13% vs. 47%, p<0.00I) and good embryo quality rates (35% vs 56%, p=0.009) were observed in patients with non-obstructive azoospermia. ln patients with obstructive azoospermia no significant differences were observed when the outcome was analyzed based on the sperm origin, from TESE or MESA ln conclusion, when combining TESE or MESA with ICSI in patients with obstructive azoospermia, the results in terms of fertilization, implantation and pregnancy rates are similar to those fo und in non-azoospermic patients that have undergone ICSI with ejaculated sperm. Non-obstructive azoospermia cases present lower fertilization, embryo quality and pregnancy rate than obstructive azoospermia, probably due to severe defects in spermatogenesis leading to poor gamete quality.