In the United States, roughly half of women are either overweight (24.5%) or obese (21.4%) when they become pregnant. Women who are obese before pregnancy are at increased risk for a number of pregnancy complications relative to normal-weight women. Specifically, obesity is associated with significantly increased maternal risks, including gestational diabetes mellitus, hypertensive disorders of pregnancy, and sleep disordered breathing. Maternal obesity is also associated with increased risks of adverse fetal outcomes, including prematurity, stillbirth, congenital anomalies, and abnormal fetal growth. In this review, we will discuss the implications of obesity with respect to antepartum care.