Men's body mass index in relation to embryo quality and clinical outcomes in couples undergoing in vitro fertilization.

OBJECTIVE To evaluate the association between men's body mass index (BMI), early embryo quality, and clinical outcomes in couples undergoing in vitro fertilization (IVF). DESIGN Prospective cohort study. SETTING Fertility clinic in an academic medical center. PATIENT(S) 114 couples who underwent 172 assisted reproduction cycles. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Fertilization rate, embryo quality, implantation rate, clinical pregnancy rate, and live birth rate. RESULT(S) The fertilization rate was higher among obese men than among normal weight men in conventional IVF cycles. No statistically significant associations were found between men's BMI and the proportion of poor-quality embryos on day 3, slow embryo cleavage rate, or accelerated embryo cleavage rate. Men's BMI was unrelated to positive β-human chorionic gonadotropin rate, clinical pregnancy rate, or live-birth rate per embryo transfer. Among couples undergoing intracytoplasmic sperm injection, the odds of live birth in couples with obese male partners was 84% lower than the odds in couples with men with normal BMI. CONCLUSION(S) Our data suggest a possible deleterious effect of male obesity on the odds of having a live birth among couples undergoing intracytoplasmic sperm injection.