Preconception Micronutrient Supplementation Positively Affects Child Development at 6 Years of Age: A Randomized Controlled Trial in Vietnam

Abstract

Abstract Objectives While there is growing evidence on the role of preconception nutrition for birth outcomes, very few studies have evaluated the effects of nutrition interventions during the preconception period on child development. This study evaluates the impact of preconception weekly multiple micronutrients (MM) or iron and folic acid (IFA) supplementation compared to FA alone on child growth and development at age 6–7y. Methods We followed 1599 offspring born to women who participated in a randomized controlled trial of preconception supplementation in Vietnam. Women received weekly supplements containing either 2800 μg FA only, 60 mg iron and 2800 μg FA, or MM (15 micronutrients including IFA), from baseline until conception; followed by daily prenatal IFA supplements until delivery. Child anthropometry and development were measured at 6–7y. Child development was measured using the Wechsler Intelligence Scale for Children IV®. Group comparisons were done using ANOVA or chi-square tests for both intention-to-treat (ITT) and per-protocol analyses (PP, women consumed supplements ≥26 wk before conception). Results The groups were similar for baseline maternal and offspring birth characteristics and age at follow-up. We found significant differences (P < 0.05) by intervention group for processing speed index for both ITT (n = 1312) and PP analyses (n = 589), and for working memory index in PP analysis. Compared to the offspring in the FA group, those in the MM group had higher processing speed (β = 1.9 for ITT, and β = 3.4 for PP analysis) and working memory indices (β = 1.5 for ITT, and β = 2.2 for PP analysis). Similar trends were found for the offspring in the IFA group compared to the FA group for working memory index (β = 1.6 for ITT, and β = 3.5 for PP analyses). There were no significant differences by treatment group for measures of verbal comprehension, perceptual reasoning index, full-scale IQ or any of the child anthropometry measures. Conclusions Preconception supplementation with MM and IFA improved some components of child development but not child size at age 6–7 y when compared to FA. These findings suggest the potential for preconception micronutrient interventions to have long-term benefits for offspring development. Funding Sources The Nestle Foundation, the Mathile Institute, and the Micronutrient Initiative.