Obesity, obstetric complications and cesarean delivery rate--a population-based screening study.

Objective: This study was undertaken to determine whether obesity is associated with obstetric complications and cesarean delivery.

Methods: A large prospective multicenter database was studied. Subjects were divided into 3 groups: body mass index (BMI) less than 30 (control), 30 to 34.9 (obese), and 35 or greater (morbidly obese). Groups were compared by using univariate and multivariable logistic regression analyses.

Results: The study included 16,102 patients: 3,752 control, 1,473 obese, and 877 morbidly obese patients. Obesity and morbid obesity had a statistically significant association with gestational hypertension (odds ratios [ORs] 2.5 and 3.2), preeclampsia (ORs 1.6 and 3.3), gestational diabetes (ORs 2.6 and 4.0), and fetal birth weight greater than 4000 g (ORs 1.7 and 1.9) and greater than 4500 g (ORs 2.0 and 2.4). For nulliparous patients, the cesarean delivery rate was 20.7% for the control group, 33.8% for obese, and 47.4% for morbidly obese patients.

Conclusion: Obesity is an independent risk factor for adverse obstetric outcome and is significantly associated with an increased cesarean delivery rate.