Antenatal Iron-Folic Acid Supplementation Improves Linear Growth and Reduces the Risk of Being Stunted or Severely Stunted in South Asian Children Less than 2 Years of Age: Pooled Analysis from Seven Countries

Abstract

Background: In South Asia, an estimated 38% of preschool-age children are stunted. We aimed to assess the effect of antenatal iron and folic acid (IFA) supplementation on stunting and smaller than average birth size in South Asian children <2 years old, the region and age-group with most stunting. Methods: The sample was 96,512 mothers with the most recent birth within two years from seven South Asian countries. Primary outcomes were stunting [length-for-age Z-score (LAZ) <-2], severe stunting and smaller than average birth size. Exposure was the use of IFA supplements. Results used multivariate regression with 14 potential confounders and adjustment for the cluster design. Findings: The prevalence of stunting was 33%, severe stunting was 14% and perceived smaller than average birth size was 22%. Antenatal IFA reduced the adjusted risk of being stunted by 8% (aRR 0·92, 95% CI 0·89, 0·95), of being severely stunted by 9% (aRR 0·91, 95% CI 0·86, 0·96) and of being smaller than average birth size by 14% (aRR 0·86, 95% CI 0·80, 0·91). The adjusted mean LAZ was significantly higher in children whose mother used IFA supplements. The most substantial risk reductions were in children whose mother used IFA in the first four months gestation and consumed 120 or more IFA supplements throughout pregnancy. Interpretation: Antenatal IFA supplementation significantly reduces the risk of stunting, severe stunting and perceived smaller than average birth size and improves LAZ in young South Asian children. The greatest impact on child growth was with IFA started early in pregnancy, and consumption of ≥120 supplements. Funding: UNICEF Regional office for South Asia. Declaration of Interest: Authors declare no conflict of interest. Ethical Approval: Country-specific ethics committees approved the surveys before the commencement of data collection, and in each survey, the respondents provided informed consent.