Effect of breastfeeding on weight retention from one pregnancy to the next: Results from the North Carolina WIC program

Abstract Objectives Pregnancy-related weight retention can contribute to obesity, and breastfeeding may facilitate postpartum weight loss. We investigated the effect of breastfeeding on long-term postpartum weight retention. Methods Using data from the North Carolina Special Supplemental Nutrition Program for Women, Infants, and Children (WIC; 1996–2004), weight retention was assessed in women aged 18 years or older who had more than one pregnancy available for analysis (n = 32,920). Using multivariable linear regression, the relationship between duration of breastfeeding after the first pregnancy and change in pre-pregnancy weight from the first pregnancy to the second pregnancy was estimated, controlling for demographic and weight-related covariates. Results Mean time between pregnancies was 2.8 years (standard deviation (SD) 1.5), and mean weight retention from the first to the second pregnancy was 4.9 kg (SD 8.7). In covariate-adjusted analyses, breastfeeding for 20 weeks or more resulted in 0.39 kg (standard error (SE) 0.18) less weight retention at the beginning of the second pregnancy relative to no breastfeeding (p = 0.025). Conclusion In this large, racially diverse sample of low-income women, long-term weight retention was lower among those who breastfed for at least 20 weeks.