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, > 0.67 standard deviations 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 US
Participants:
Mother-infant dyads (n=256)
Results:
Most participants were African American (48%) or Latina (34%). Eighty-one percent were participating in the Special Supplemental Nutrition Program for Women, Infants, and Children. Infants were breastfed for a median duration of 4.75 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 (β = 0.045, SE = 0.013, p =.001) or 3-6 months (β = 0.054, SE = 0.016, p =.001). Thirty-six percent of the infants experienced RWG. RWG was more common among infants who were breastfed for 2 months or less than 6+ month breastfed group (RR = 1.68, CI95: 1.03–2.74, p = 0.03).
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.