(572) Association of duration of breastfeeding with child neurodevelopment at 18 to 30 months

Although breastfeeding is associated with many maternal and infant health benefits, it is unknown whether the duration of breastfeeding is associated with offspring neurodevelopmental outcomes. We evaluated the association of duration of breastfeeding with neurodevelopmental outcomes at 18 to 30 months of age.

Study Design:
This is a secondary analysis of a multisite, prospective observational study assessing outcomes after SARS-CoV-2 vaccination during or up to 30 days before pregnancy. This analysis evaluated neurodevelopmental outcomes of 18-30 month old children born at term as singleton gestations, who initiated breastfeeding, had a known breastfeeding duration, and had complete primary outcome data. At 18-30 months, caregivers completed study visits that included breastfeeding queries and measures of neurodevelopment. The primary outcome was the Ages and Stages Questionnaire version 3 (ASQ) total score. Secondary outcomes included domain-specific ASQ scores, the Child Behavior Checklist (CBCL), Modified Checklist for Autism in Toddlers (MCHAT), and Early Childhood Behavior Questionnaire (ECBQ). Differences in each outcome were compared by breastfeeding duration (< 3 versus ≥3 months), adjusting for maternal age, education, SARS-CoV-2 vaccination during pregnancy, and study center.

Results:

Of 511 participants in the primary study, 428 (84%) were eligible for inclusion. A majority (N=292, 68%) breastfed for ≥3 months. Those who breastfed ≥3 months were older, more likely to have some college education, and to be multiparous. There was no difference in offspring ASQ total score by breastfeeding duration, although those who were breastfed ≥3 months had a reduced risk of a score > 2 SDs below mean on the ASQ problem-solving domain (aRR 0.3, 95% CI 0.1-0.6) (Table 1). No clinically significant differences were noted in total or component scores for the CBCL, MCHAT, or ECBQ (Table 2).

Conclusion:

Among children born at term who initiated breastfeeding, there was no association between being fed breastmilk for ≥3 months and neurodevelopmental outcomes at 18-30 months of age.