AIM: This study investigated whether duration of full breastfeeding is associated with child neuropsychological development and whether this association is explained by social, psychological, and nutritional factors within families.
METHOD: Participants in this study were a population-based birth cohort in the city of Sabadell (Catalonia, Spain). Females were recruited during the first trimester of pregnancy between July 2004 and July 2006. Information about parental characteristics and breastfeeding was obtained through questionnaires. Full breastfeeding was categorized as never, short term (less than or equal to 4mo), long term (4-6mo), or very long term (>6mo). A trained psychologist assessed the neuropsychological development of children at 4 years of age (n=434) using the McCarthy Scales of Children's Abilities (MSCA).
RESULTS: Full breastfeeding showed an independent association with child general MSCA scores after adjusting for a range of social, psychological, and nutritional factors (>6mo, coefficient=7.4 [95% confidence interval=2.8-12.0], p=0.011). Maternal social class, education level, and IQ were also associated with child neuropsychological scores, but did not explain breastfeeding associations. Omega-3 (n3) fatty acid levels were not associated with child neuropsychological scores.
INTERPRETATION: Very long-term full breastfeeding was independently associated with neuropsychological functions of children at 4 years of age. Maternal indicators of intelligence, psychopathology, and colostrum n3 fatty acids did not explain this association.
