Résumé
Epidemiological studies have reported that breastfed children have improved psychomotor development compared to never breastfed children. Human studies suggest that polyunsaturated fatty acids (PUFA), especially long chain PUFA (LC-PUFA) which are highly contained in breast milk, could explain this link, since they are needed for pre-and postnatal brain development. Our aim was to study the relationships between several measures of pre-and postnatal exposures to PUFA and child's psychomotor development at 2 and 3 years in the EDEN cohort. We evaluated breastfeeding duration, colostrum PUFA levels and maternal dietary PUFA intake during pregnancy, that we related with three scores of psychomotor development, after taking into account potential confounders. Breastfeeding duration was positively associated with psychomotor development. No relationship was found with both pre-and postnatal exposure to LC-PUFA. However, the maternal dietary omega-6/omega-3 ratio was negatively associated with psychomotor development, mainly driven by intake in linoleic acid (LA). Among breastfed children, linoleic acid levels were negatively associated with psychomotor development. Furthermore, children exposed to the highest colostrum LA levels tended to score closer to never breastfed children than to children exposed to the lowest colostrums LA levels. Taken together, these results do not provide evidence in favour of a positive role of pre-and postnatal exposure to LC-PUFA on later psychomotor development, but highlight a potential negative role of being exposed in early life to high LA levels. From a public health perspective, this work reiterates the need to promote breastfeeding duration, and to monitor the balance of PUFA intake during pregnancy and lactation periods.