Prenatal micronutrients improve function in offspring

Giving folic acid and iron supplements to pregnant women in areas where the community diet may be low in iron increases intellectual and motor function in their children, according to a recent study.

Researchers from Johns Hopkins University, Baltimore, evaluated intellectual and motor function in 676 children, 7 to 9 years of age, born to rural Nepalese women who had participated in a community-based, double-blind, randomized, controlled trial of prenatal micronutrient supplementation. From early pregnancy through 3 months postpartum, the women had received vitamin A alone or in combination with iron/folic acid, iron/folic acid/zinc, or iron/folic acid/zinc plus 11 other micronutrients.

“Aspects of intellectual functioning, including working memory, inhibitory control, and fine motor functioning, among offspring were positively associated with prenatal iron/folic acid supplementation in an area where iron deficiency is prevalent,” writes lead author Parul Christian, DrPH.

The difference across outcomes between the children of women who received iron/folic supplementation and those whose mothers received only vitamin A was significant (Bonferroni-adjusted P<.001). Children of women in the iron/folic acid group had a mean score of 51.7 on the Universal Nonverbal Intelligence Test, compared with 48.2 for children of the control group, with an adjusted mean difference of 2.38 (95% Confidence Interval, 0.06-4.70; P=.04).

The iron/folic acid group also scored higher than controls on executive function (measured by the go/no go test, Stroop test, and backward digit span) and motor function (assessed by the Movement Assessment Battery for Children and the finger-tapping test).

No significant differences in outcomes were found between the other supplementation groups and controls in any of the measures.

The study was published in JAMA 2010;304(24):2716-2723.