Breastfeeding duration and associations with prevention of accelerated growth among infants from low-income, racially and ethnically diverse backgrounds

Objective: To describe breastfeeding rates from early to late infancy and to examine associations between breastfeeding duration and infant growth, including rapid weight gain (RWG, > 0<middle dot>67 SD increase in weight-for-age Z-score), among infants from low-income, racially and ethnically diverse backgrounds.Design: A short, prospective cohort study was conducted assessing breastfeeding status at infant ages 2, 4, 6, 9 and 12 months. Infant length and weight measurements were retrieved from electronic health records to calculate weight-for-length Z-scores and the rate of weight gain.Setting: Pediatric clinic in the Southeastern USA.Participants: Mother-infant dyads (n = 256).Results: Most participants were African American (48 %) or Latina (34 %). Eighty-one per cent were participating in the Special Supplemental Nutrition Program for Women, Infants and Children. Infants were breastfed for a median duration of 4<middle dot>75 months, with partial more common than exclusive breastfeeding. At 12 months, 28 % of the participants were breastfeeding. Infants breastfed beyond 6 months had significantly lower growth trajectories than infants breastfed for 0-2 months (beta = 0<middle dot>045, SE = 0<middle dot>013, P = 0<middle dot>001) or 3-6 months (beta = 0<middle dot>054, SE = 0<middle dot>016, P = 0<middle dot>001). Thirty-six per cent of the infants experienced RWG. RWG was more common among infants who were breastfed for 2 months or less than 6+ month breastfed group (relative risk = 1<middle dot>68, CI95 (1<middle dot>03, 2<middle dot>74), P = 0<middle dot>03).Conclusions: Breastfeeding beyond 6 months is associated with the prevention of accelerated growth among infants from low-income, racially and ethnically diverse backgrounds, suggesting progress toward health equity.