Obstetric outcomes after in vitro fertilization in obese and morbidly obese women

OBJECTIVE: In addition to numerous health detriments caused by obesity, fertility and pregnancy success may also be compromised. The aims of this study were to compare the effects of obesity and morbid obesity on in vitro fertilization (IVF) outcomes. We also investigated the effects of obesity on obstetric outcomes after IVF treatment. METHODS: Retrospective study of women less than 38 years of age during their first fresh IVF cycle (January 1995 to April 2005). RESULTS: A total of 1,293 women were included in the study, with 236 obese women (body mass index [BMI] = 30-39.9) and 79 morbidly obese women (BMI 2: 40). The morbidly obese group had a 25.3% IVF cycle cancellation rate compared with 10.9% in normal-weight women (odds ratio 2.73, 95% confidence interval 1.49-5.0), P <.001). Morbidly obese women without polycystic ovarian syndrome had an even higher cancellation rate (33%). Women with higher BMI required significantly more days of gonadotropin stimulation but had lower peak estradiol levels (P <.001). There were no significant differences in clinical pregnancy or delivery rates between the four BMI groups. Of the women who delivered, there was a significant linear trend for risk of preeclampsia, gestational diabetes, and cesarean delivery with increasing BMI (P <.03). CONCLUSION: We report a significantly higher risk for IVF cycle cancellation in morbidly obese patients with no effect of BMI on clinical pregnancy or delivery rate. However, obese and morbidly obese subjects had a significantly higher risk for obstetric complications. This target population should be aggressively counseled regarding their increased obstetric risk and offered treatment options for weight reduction before the initiation of fertility therapy.