PURPOSE OF REVIEW The rates of obesity are increasing rapidly in the United States and other countries. Because obesity is a major factor in the development of many chronic diseases, it is an important individual and public health issue. This review focuses on the pregnancy complications associated with maternal obesity. RECENT FINDINGS Maternal obesity adversely impacts pregnancy outcome primarily through increased rates of hypertensive disease (chronic hypertension and pre-eclampsia), diabetes (pregestational and gestational), cesarean section and infections. It is associated with a higher rate of venous thromboembolic disease and respiratory complications, and may be an independent risk factor for neural tube defects, fetal mortality and preterm delivery. Maternal obesity also increases the risk of delivering a large for gestational age or macrosomic neonate, who is in turn at an increased risk of subsequent childhood obesity and its associated morbidity. SUMMARY Recommendations regarding the counselling of obese pregnant women and specific guidelines for the obstetrician, family physician, or midwife managing the pregnancy are presented. Cultural and political changes with the potential to decrease the epidemic of obesity in our society are discussed.