Effects of women's body mass index on in vitro fertilization success: a retrospective cohort study

Background: The purpose of this study is to evaluate the influence of body mass index (BMI) on the reproductive outcomes and clinical pregnancy rate after in vitro fertilization (IVF). Methods: This retrospective study was performed on 230 women undergoing first cycle of standard IVF between October 2008 and February 2010. The patients were classified into three groups according to their BMI (BMI < 20 kg/m(2), 20 kg/m(2) < BMI < 27.9 kg/m(2) and BMI > 28 kg/m(2)). Information regarding clinical pregnancy was compared within these three groups. Results: There was no significant relation between BMI and age, the number of aspirated follicles, transferred embryos, mature oocytes, days of taking human menopausal gonadotropin (HMG) ampules and the total number of HMG ampules among three BMI studied groups. Statistically significant difference was detected between BMI and endometrial thickness. Conclusions: BMI has no effect on IVF outcomes and clinical pregnancy after IVF. However, losing weight in obese women seems reasonable to prevent possible obstetrics complications.