['To determine the subgroup of patients in whom office hysteroscopy should be routinely performed before an in vitro fertilization (IVF) program.', 'Retrospective cohort analysis.', 'Tertiary education and research hospital.', 'Two hundred twenty-three patients who underwent a uterine evaluation by office hysteroscopy before the IVF and embryo transfer cycle.', 'The office hysteroscopy was performed in the follicular phase of the menstrual cycle before the IVF cycle.', 'The office findings: number of polyps, number of multiple polyps, and polyp size.', 'Patients with polycystic ovary syndrome (PCOS) had a higher number of endometrial polyps, but the difference was not statistically significant (28.9% vs. 18.3%). When comparing the patients according to BMI, patients with BMI >or=30 had a statistically significantly higher number of endometrial polyps versus BMI <30 (52% vs. 15%). On the other hand, obesity was positively correlated with the occurrence of polyps, size of the polyps, and occurrence of multiple number of polyps in the correlation analysis. In addition, logistic regression analysis using age, obesity, duration of infertility, and estradiol levels revealed that obesity was an independent prognostic factor for the development of endometrial polyps.'] Is body mass index an independent risk factor for the development of endometrial polyps in patients undergoing in vitro fertilization?