Preschool Iron‐Folic Acid and Zinc Supplementation in Children Exposed to Iron‐Folic Acid In Utero Confers No Added Cognitive Benefit in Early School‐age

Abstract

Antenatal iron-folic acid supplementation improves aspects of intellectual, executive, and fine motor function among school-age offspring in rural Nepal. Using data from two RCTs, we examined whether combinations of added zinc to the maternal supplement (M-IFAZn) and preschool supplementation from 12–36 mo with iron-folic acid (C-IFA) +/− zinc (C-IFAZn) enhance cognitive outcomes beyond that seen with antenatal maternal iron-folic acid (M-IFA) alone. Relative to the M-IFA group, child supplementation did not impact scores on the UNIT (Universal Nonverbal Intelligence Test), Stroop and go/no go tests. However, children in the C-IFAZn group had lower scores on the backward digit span (adj −0.31, 95% CI: −0.59, −0.03) and movement assessment battery (adj 1.44, 95% CI: 0.20, 2.68). The combinations of C-IFA (−2.36, 95% CI: −4.14, −0.58), C-IFAZn (−1.92, 95% CI: −3.22, −0.63), and M-IFAZn/C-IFAZn (−2.04, 95% CI: −3.69, −0.44) produced lower finger tapping test scores after adjustment. Preschool iron-folic acid +/− zinc to children exposed to iron-folic acid in utero confers no additional benefit to cognitive outcomes assessed in early school age and may even diminish the positive effects of maternal iron-folic acid; mechanisms underlying this warrant investigation. Support: NICHD, Gates Foundation.