According to the 1999–2002 National Health and Nutrition Examination Survey, the prevalence of overweight or obesity in adults aged older than 20 years was 65.0%, and the prevalence of obesity was 30.0%.2 Associated with an increase in obesity is a concomitant increase in the prevalence of many chronic health conditions, such as diabetes mellitus, hypertension, and cardiovascular disease. In women of reproductive age, obesity has also been associated with an increased rate of preeclampsia, operative vaginal deliveries, cesarean delivery, and postoperative complications.3 Therefore, obesity is a major concern in pregnancy.