Effects of prenatal fish-oil and 5-methyltetrahydrofolate supplementation on cognitive development of children at 6.5 y of age.

Randomized study of healthy pregnant women from three European centers with singleton pregnancies, with offspring followed to 6.5 years of age. Child cognitive development was assessed with the Kaufman Assessment Battery for Children.

Participants were assigned to prenatal oral supplementation from the 20th week of pregnancy until delivery in one of three active regimens: modified fish oil providing 500 mg DHA plus 150 mg eicosapentaenoic acid daily, fish oil plus 400 microg 5-methyltetrahydrofolate daily, or 400 microg 5-methyltetrahydrofolate daily alone.

Prenatal fish oil and or 5-methyltetrahydrofolate supplementation did not improve cognitive performance at 6.5 years. Mental Processing Composite scores on the Kaufman Assessment Battery for Children were similar across groups: 110 11 for fish oil, 108 10.5 for fish oil plus 5-methyltetrahydrofolate, and 108 12 for 5-methyltetrahydrofolate alone, with no between-group difference (P = 0.821). The broader paper concluded there were no significant cognitive differences among the four groups, although higher maternal DHA status at delivery was associated with a higher likelihood of the child scoring above the 50th percentile on Mental Processing Composite.

The packet does not report the active-arm sample sizes or complete sex data, limiting precision and subgroup interpretation. Adverse events were not reported, and the analysis provides limited information on adherence and other potential confounders. Cognitive outcomes were assessed at a single long-term follow-up point, which may miss smaller or earlier effects.