Breastfeeding and Responsive Parenting as Predictors of Infant Weight Change in the First Year.

Objective To test breastfeeding duration and responsive parenting as independent predictors of infant weight change from birth to 12 months, and to test the moderating effect of a tiered parenting intervention on relations between breastfeeding and responsive parenting in relation to infant weight change. Methods Mother-infant dyads (N = 403) were participants in the ongoing Smart Beginnings (SB) randomized controlled trial testing the impact of the tiered SB parenting model that incorporates two evidence-based interventions: Video Interaction Project (VIP) and Family Check-Up (FCU). The sample was low income and predominantly Black and Latinx. Responsive parenting variables (maternal sensitivity and intrusiveness) came from coded observations of mother-infant interactions when infants were 6 months. Continuous weight-for-age (WFA) z-score change and infant rapid weight gain (RWG) from 0 to 12 months were both assessed. Results Longer breastfeeding duration was significantly associated with less WFA z-score change. The relationship between breastfeeding duration and WFA z-score change was significant only for infants in the intervention group. Intrusive parenting behaviors were also associated with greater WFA z-score change after accounting for breastfeeding duration. Conclusions This study is one of the first to test both breastfeeding and parenting in relation to infant weight gain in the first year. Findings may have implications for family-focused child obesity prevention programs.