Infant feeding mode is associated with differences in postpartum weight change and percent body fat from 2 to 16 weeks

Excessive gestational weight gain and postpartum weight change (PPWC) are contributing factors to the prevalence of obesity among women of childbearing age. This study investigated whether mothers (N=77) PPWC and percent body fat (%body fat) differed by infant feeding mode (predominantly breastfeeding vs. formula-feeding). Formula-feeding mothers tended to be obese (BMI > 30.0), Black, and WIC participants. Anthropometry and %body fat (by air displacement plethysmography) were assessed at 2, 8 and 16 weeks postpartum. Repeated measures ANCOVA adjusting for self-reported pre-pregnancy weight revealed that breastfeeding mothers weight and %body fat declined from 2 to 16 weeks (-3.63 kg, -2.05 %body fat), while formula-feeding mothers weight and %body fat increased (0.26 kg, 0.19 %body fat). 2 tests revealed that formula-feeding mothers were heavier on average at all time points, and retained more weight and %body fat, outcomes that may increase the risk of maternal obesity.