ABSTRACT: The obesity epidemic continues unabated. Among American women aged 20–39 years, 31.9% were obese in 2009–2010 1. Obese women are at risk of multiple medical comorbidities and pregnancy-related complications. Therefore, obstetrician–gynecologists should be familiar with current approaches to the prevention and management of obesity. Appreciation of the risks of obesity and associated diseases is essential. The etiology of obesity is multifactorial and includes genetic makeup, behavior and environment as they affect metabolism, physical activity, and dietary intake. Informal office counseling usually is the initial approach to managing weight. When this fails, structured weight loss programs that include diet modification, medications, exercise, and behavioral strategies may be used. However, because of the limited long-term effectiveness of these modalities, bariatric surgery is becoming a preferred option. Several surgical approaches are available. Obstetrician–gynecologists should be familiar with the advantages and disadvantages of each procedure, the importance of long-term management, and principles of pregnancy care in these individuals.