[Effect of women's weight on the success rate of in vitro fertilization]

Abstract

Objective: To examine the effect of women's weight on the success rate of in vitro fertilization.

Patients and methods: Single centre retrospective study of a continuous series of 846 patients who underwent 1444 in vitro fertilization or ICSI cycles. The outcomes of each cycle was analysed as a function of the woman's body mass index (BMI). Three groups were defined: (1) underweight (BMI<18 kg/m2, n=68 cycles, 43 women), (2) normal BMI (18 < or =BMI<25, n=1045 cycles, 607 women), (3) overweight or obese women (IMC > or =25, n=331 cycles, 196 women).

Main outcome measurement: Live birth rate per cycle.

Results: In group 3, the live birth rate per cycle (10,6% [95% confidence interval: 7,3-13,9]) was significantly lower than in group 2 (16,6% [14,3-18,8]). There was a non-significant trend towards a decreased live birth rate in group I (11,8% [4,1-19,4]). In group 3, the cancellation rate (30,8% [25,8-35,8]) was significantly greater than in group 2 (19,6% [17,2-22]), the pregnancy per oocyte pick-up rate was lower (19,9% versus 24,6%) and the early miscarriage rate was increased (26,9% versus 15,7%) without reaching statistical significance.

Discussion and conclusion: The live birth rate was decreased among overweight or obese women. This could be mediated by impairment of response to ovarian stimulation, oocyte quality, or implantation abnomalies.