Decreased fertilization rate and embryo quality after ICSI in oligozoospermic men with microdeletions in the azoospermia factor c region of the Y chromosome

Microdeletions of the azoospermia factor (AZF) region of the Y chromosome o ccur in between 1 and 29% of oligozoospermic and azoospermic men, and most deletions are found in the AZFc region. These men can father children when intracytoplasmic sperm injection (ICSI) is used, but the success rate is un clear. Thus, the success rate of 19 ICSI treatments in eight couples with a microdeletion in the AZFc region of the Y chromosome was analysed retrospe ctively. These were compared with a control group of 239 ICSI treatments in 107 couples undergoing ICSI treatment with ejaculated spermatozoa. The fer tilization rate was significantly lower in the group of Y-deleted men (55%; 95% CI: 41-69%) compared with controls (71%; 95% CI: 67-74%; P < 0.01). Th e embryo quality was also significantly poorer among Y-deleted men (P < 0.0 01). Pregnancy, implantation and take-home baby rates were not significantl y lower in the Y-deleted group. This study shows that ICSI in oligozoosperm ic men with microdeletions in the AZFc region of the Y chromosome leads to a lower fertilization rate and poorer embryo quality.