ABSTRACT
Sperm cryopreservation causes extensive damage to sperm membranes and its ultrastructural morphology, affecting the fertilization ability by decreasing the percentage of normal intact acrosomes and consequently the acrosine activity. This retrospective study aims at detecting the effect of sperm cryopreservation on the baby's sex after intracytoplasmic sperm injection [ICSI] in terms of the susceptibility of X versus Y chromosome baring spermatozoa to cryopreservation. This retrospective study included 87 ICSI cycles performed with post-thawed spermatozoa. The patients were classified into two groups [I and II] according to the total sperm count before freezing. This study included 87 ICSI cycles performed with post-thawed spermatozoa. Patients were classified into two groups [I and II] according to the total sperm count before freezing. Group I included 43 patients with a sperm count less than 0.1 × 10[6]/sample [countable samples]. Group II included 44 patients with a sperm count more than 0.1 × 10[6]/sample [uncountable samples]. The numbers of fertilized M II, good embryos, clinical pregnancy, and male babies were significantly higher in group I compared with group II. ICSI using post-thawed spermatozoa of countable samples yielded a higher male sex ratio [80.8%] compared with uncountable samples [28.6%]. Thus, spermatozoa that successfully survived the freeze-thaw procedure exhibited an improved chromatin structure and nuclear maturity. These data suggest that sperm cryopreservation may improve the fertilization rate, enhance early embryo development parameters, as well as pregnancy outcome after ICSI