Time to change weight gain recommendations for pregnant women with obesity.

Obesity during pregnancy is a major health problem in the United States. In this issue of the JCI, Most et al. fill an important gap in our understanding of energy homeostasis in pregnancy. The researchers measured energy intake, energy expenditure, and body composition in obese pregnant women. They demonstrated that energy intake need not increase in order for obese women to gain the recommended amounts of weight during pregnancy. Additionally, all of the gestational weight gain scenarios (inadequate, recommended, or excess) resulted in similar maternal and fetal perinatal outcomes. This evidence should guide new recommendations on this important topic.