Postpartum Weight Retention Risk Factors and Relationship to Obesity at 1 Year

OBJECTIVE: To explore risk factors for postpartum weight retention at 1 year after delivery in predominantly low-income women. METHODS: Data were collected from 774 women with complete height and weight information from participants in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Community Child Health Network, a national five-site, prospective cohort study. Participants were enrolled primarily in the hospitals immediately after delivery. Maternal interviews conducted at 1, 6, and 12 months postpartum identified risk factors for weight retention and included direct measurement of height and weight at 6 and 12 months. Logistic regression assessed the independent contribution of postpartum weight retention on obesity. RESULTS: Women had a mean prepregnancy weight of 161.5 lbs (body mass index [BMI] 27.7). Women gained a mean of 32 lbs while pregnant and had a 1-year mean postpartum weight of 172.6 lbs (BMI 29.4). Approximately 75% of women were heavier 1 year postpartum than they were prepregnancy, including 47.4% retaining more than 10 lbs and 24.2% more than 20 lbs. Women retaining at least 20 lbs were more often African American, younger, poor, less educated, or on pubic insurance. Race and socioeconomic disparities were associated with high prepregnancy BMI and excessive weight gain during pregnancy, associations that were attenuated by breastfeeding at 6 months and moderate exercise. Of the 39.8 with normal prepregnancy BMI, one third became overweight or obese 1 year postpartum. CONCLUSION: Postpartum weight retention is a significant contributor to the risk for obesity 1 year postpartum, including for women of normal weight prepregnancy. Postpartum, potentially modifiable behaviors may lower the risk.