Effects of Prenatal DHA Dose on Infant Visual Attention

Prenatal supplementation with docosahexaenoic acid (DHA) has been reported to improve cognitive outcomes in infancy and early childhood in some studies. Existent studies have examined the effects of some dose of DHA against a true placebo; this report is the first to describe the effects of different doses of prenatal DHA on infant visual attention at 4 and 6 months of age. In a follow-up to a Phase III registered clinical trial (NCT02709239) designed to evaluate the effects of two prenatal doses of DHA supplementation (200 or 800 mg daily) on maternal physiology and fetal neurodevelopment, we assessed 215 infants delivered to these mothers at 4 and 6 months on a visual habituation task augmented with heart rate (HR) to assess visual stimulus processing, and a gap–overlap task to assess engagement and disengagement of attention. Infants of mothers supplemented with 800 mg/day of DHA had shorter look durations (indicative of more rapid visual learning) during habituation at both ages and a somewhat more mature pattern of HR-defined phases of attention. However, DHA dose did not affect infant HR, nor did it affect infant performance in the gap–overlap attention task. Results are consistent with positive effects of prenatal DHA supplementation on later outcomes, with higher benefit seen for a higher dose.