Body mass index is negatively correlated with the response to controlled ovarian stimulation but does not influence oocyte morphology in ICSI cycles.

OBJECTIVE To investigate whether or not body mass index (BMI) is associated with oocyte dysmorphisms. STUDY DESIGN This retrospective study enrolled 1105 patients undergoing intracytoplasmic sperm injection (ICSI). The correlation between BMI and the response to controlled ovarian stimulation (COS) and ICSI outcomes was analysed. Oocyte morphology was determined in metaphase II (MII) oocytes retrieved from all cycles. The influence of BMI on the odds of having oocyte dysmorphism was also studied. RESULTS A negative correlation was found between BMI and the number of oocytes retrieved, MII oocytes, oocytes injected, embryos obtained, high-quality embryos and oocyte recovery rate. In addition, a trend towards a negative correlation between BMI and implantation rate was observed. However, BMI did not influence oocyte dysmorphisms. CONCLUSIONS A negative correlation was found between BMI and the response to COS, and a trend towards a negative correlation was observed between BMI and implantation rate in the ICSI cycles. However, oocyte dysmorphisms were not influenced by BMI and, therefore, do not account for the reduced ICSI outcomes.