Obesity and in vitro fertilization: negative influences on outcome.

Objective: To determine the influence of body mass index (BMI) on in vitro fertilization (IVF) outcome by studying a large cohort of good-prognosis IVF patients.

Study Design: This was a retrospective study at a university-based IVF center evaluating 920 good-prognosis patients (< 40 years, all with normal ovarian reserve) undergoing luteal leuprolide down-regulation and gonadotropin stimulation for IVF and evaluating IVF outcome, including response to stimulation, cancellation rates and pregnancy outcome based on obesity status.

Results: One hundred forty-eight (16.