To date, little is known about the impact of the male factor on IVF outcomes such as embryo developmental competence and, more importantly, on aneuploidy rate.
GeneraLife clinical researchers have published a study on this topic in the ‘Fertility and Sterility’ journal, and the conclusion was that male factor has influence only on some phases of the path.
In this study 1,219 cycles conducted for 1,090 couples were included, and the ICSI (intracytoplasmic sperm injection) outcomes were evaluated according to seminal characteristics and male partner personal features.
The results of this study show that in the early stages of in vitro embryonic development there is a difference between azoospermia, oligoasthenoteratozoospermia and normozoospermia subjects regarding oocyte fertilization and blastocyst development.
Significantly lower fertilization rates were observed when testicular spermatozoa from men with non-obstructive azoospermia were used for ICSI.
The blastocyst rate per fertilized oocyte was significantly reduced in moderate male factor and nonobstructive azoospermia compared with normozoospermia (48.6% and 40.6% vs. 49.3%).
The timing of blastocyst development also was affected in obstructive azoospermia and non-obstructive azoospermia. When the analysis was performed per obtained blastocyst, however, no correlation between male factor and euploidy rate was observed. Embryo transfers also resulted in similar live birth and miscarriage rates.
No impact of sperm factor on obstetrical/perinatal outcomes was observed. So, in conclusion, this study showed that severe male factor impacts fertilization and basculation, but not chromosomal and reproductive competence of the blastocysts obtained.