Y chromosome deletions in azoospermic and severely oligozoospermic men undergoing intracytoplasmic sperm injection after testicular sperm extraction

Y chromosome deletions encompassing the AZFc region have been reported in 1 3% of azoospermic men and 7% of severely oligozoospermic men. We examined t he impact of these Y deletions on the severity of testicular defects in 51 azoospermic men undergoing intracytoplasmic sperm injection (ICSI) after te sticular sperm extraction (TESE) and 30 men with severe oligozoospermia und ergoing ICSI after ejaculation of spermatozoa. In addition, five azoospermi c patients shown previously to have Y chromosome deletions underwent histol ogical evaluation of their previously obtained testis biopsy specimens. A f urther 27 azoospermic men underwent TESE-ICSI, but not Y chromosome DNA tes ting. Ten of 51 azoospermic men (20%) who underwent TESE-ICSI and Y-DNA tes ting were found to be deleted for portions of the Y chromosome AZFc region. Of these 10, five had spermatozoa retrievable from the testis, and in two cases the wives became pregnant. Of the 41 azoospermic men with no Y chromo some deletion, 22 (54%) had spermatozoa retrievable from the testis, and in 12 cases (29%) the wives became pregnant. Four of 30 (13%) severely oligoz oospermic patients were found to be deleted for AZFc and in three (75%) of these pregnancy was achieved. The other 26 severely oligozoospermic couples who had no AZFc deletions underwent ICSI, and 12 (46%) have an ongoing or delivered pregnancy. The embryo implantation rate was not significantly dif ferent for azoospermic (22%), oligozoospermic (16%), Y-deleted (14%) or Y-i ntact (18%) men. Of the total of 19 infertile men who had Y chromosome dele tions, 14 had deletions within Y chromosome intervals 6D-6F, in the AZFc re gion. Twelve of those 14 had some spermatozoa (however few in number) in th e ejaculate or testis. Five of the Y-deleted men had deletions that extende d more proximally on the Y chromosome, and in none of these could any sperm atozoa be observed in either ejaculate or testis. These results support the concept that, in azoospermic or oligozoospermic men with Y chromosome dele tions limited to intervals 6D-6F (AZFc), there are generally very small num bers of testicular or ejaculated spermatozoa. Larger Y deletions, including and extending beyond the AZFc region and encompassing more Y genes, tend t o be associated with a total absence of testicular spermatozoa. In those ca ses where spermatozoa were retrieved, the presence of Y deletions had no ob vious impact on fertilization or pregnancy rate.