Maternal body mass index is not associated with increased rates of maternal embryonic aneuploidy

Objective To evaluate the relationship between maternal body mass index (BMI) and embryonic aneuploidy of maternal origin. Design Retrospective cohort analysis. Setting University hospital-based reproductive center. Patients Maternal origin of aneuploidy was available for 453 cycles and 1,717 embryos. Interventions Data regarding BMI were collected before egg retrieval. Comparison groups included underweight (BMI, <18.5 kg/m 2 ), normal weight (BMI, 18.5–24.9 kg/m 2 ), overweight (BMI, 25–29.9 kg/m 2 ), and obese (BMI, ≥30 kg/m 2 ). Overall embryonic aneuploidy and maternal aneuploidy rates were compared. The aneuploidy rate was the number of embryos with either maternal or mixed (maternal and paternal) aneuploidy divided by the total number of embryos tested. Main Outcome Measures Overall embryonic aneuploidy and maternal aneuploidy rates. Results Maternal aneuploidy rate was 51.5% for BMI of ≥30 kg/m 2 and 39.3% for BMI of <30 kg/m 2 . Female age as well as several in vitro fertilization characteristics were significantly different across groups and were included in the adjusted model. Both the overall embryonic aneuploidy rate (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.11–1.59) and the maternal aneuploidy rate (OR, 1.64; 95% CI, 1.25–2.16) increased with increasing maternal BMI. However, after controlling for significant confounders, BMI did not significantly predict the rate of maternal aneuploidy (OR, 1.16; 95% CI, 0.85–1.59). Conclusions Maternal BMI did not correlate with embryonic aneuploidy of maternal origin after adjusting for confounders.