Effect of body mass index on in vitro fertilization outcomes in women

Obesity has become a major health problem across the world. In women, it is known to cause anovulation, subfecundity, increased risk of fetal anomalies and miscarriage rates. However, in women going for assisted reproduction the effects of obesity on egg quality, embryo quality, clinical pregnancy, live birth rates are controversial.

To assess the effect of women's body mass index (BMI) on the reproductive outcome of non donor In vitro fertilization (IVF)/Intracytoplasmic sperm injection (ICSI). The effects of BMI on their gonadotrophin levels (day 2 LH, FSH), gonadotrophin dose required for ovarian stimulation, endometrial thickness and oocyte/embryo quality were looked at, after correcting for age and poor ovarian reserve.

Retrospective study of medical records of 308 women undergoing non donor IVF cycles in a University affiliated teaching hospital. They were classified into three groups: normal weight (BMI<25 kg/m(2)), overweight (BMI>25 <30 kg/m(2)) and obese (BMI>30 kg/m(2)). All women underwent controlled ovarian hyper stimulation using long agonist protocol.

There were 88 (28.6%) in the normal weight group, 147 (47.7%) in the overweight and 73 (23.7%) in the obese group. All three groups were comparable with respect to age, duration of infertility, female and male causes of infertility. The three groups were similar with respect to day 2 LH/FSH levels, endometrial thickness and gonadotrophin requirements, oocyte quality, fertilization, cleavage rates, number of good quality embryos and clinical pregnancy rates.

Increase in body mass index in women does not appear to have an adverse effect on IVF outcome. However, preconceptual counselling for obese women is a must as weight reduction helps in reducing pregnancy-related complications.