Docosahexaenoic acid supplementation and time at achievement of gross motor milestones in healthy infants: a randomized, prospective, double-blind, placebo-controlled trial.

Randomized, prospective, double-blind, placebo-controlled trial in healthy term singleton infants in northern Italy. Infants were assessed during the first year of life for gross motor milestone attainment, with baseline characteristics reported for the active and placebo groups.

Daily oral docosahexaenoic acid (DHA) supplementation was given as 1 mL of liquid study preparation containing 20 mg DHA and 400 IU vitamin D3, started within 24 hours after discharge and continued throughout the first year of life. The placebo preparation contained 400 IU vitamin D3 without DHA.

DHA supplementation produced a small earlier attainment of sitting without support, but it did not significantly change later gross motor milestones. Sitting without support occurred at a median of 26 weeks with DHA versus 27 weeks with placebo (P < 0.0001; adjusted hazard ratio 1.3, 95% CI 1.2 to 1.5). Hands-and-knees crawling was 39 versus 40 weeks (P = 0.090), standing alone 49 versus 49 weeks (P = 0.075), and walking alone 55 versus 56 weeks (P = 0.060). No adverse events related to the intervention were observed.

The clinically meaningful impact of the 1-week earlier sitting milestone is uncertain, and there were no significant benefits for later gross motor milestones. Generalizability is limited because the trial enrolled healthy term singleton infants from a single region in northern Italy, with white parents as an inclusion criterion. Longer-term developmental outcomes were not established.