Pregnancy outcomes decline with increasing recipient body mass index: an analysis of 22,317 fresh donor/recipient cycles from the 2008-2010 Society for Assisted Reproductive Technology Clinic Outcome Reporting System registry.

Objective: To examine the effect of recipient body mass index (BMI) on IVF outcomes in fresh donor oocyte cycles.

Design: Retrospective cohort study.

Setting: Not applicable.

Patient(s): A total of 22,317 donor oocyte cycles from the 2008-2010 Society for Assisted Reproductive Technology Clinic Outcome Reporting System registry were stratified into cohorts based on World Health Organization BMI guidelines. Cycles reporting normal recipient BMI (18.5-24.9) were used as the reference group.

Intervention(s): None.

Main Outcome Measure(s): Implantation rate, clinical pregnancy rate (PR), pregnancy loss rate, live birth rate.

Result(s): Success rates and adjusted odds ratios with 95% confidence intervals for all pregnancy outcomes were most favorable in cohorts of recipients with low and normal BMI, but progressively worsened as BMI increased.

Conclusion(s): Success rates in recipient cycles are highest in those with low and normal BMI. Furthermore, there is a progressive and statistically significant worsening of outcomes in groups with higher BMI with respect to clinical pregnancy and live birth rate.