Effects of alternative maternal micronutrient supplements on low birth weight in rural Nepal: double blind randomised community trial

Abstract
Objective: To assess the impact on birth size and risk of low birth weight of alternative combinations of micronutrients given to pregnant women. Design: Double blind cluster randomised controlled trial. Setting: Rural community in south eastern Nepal. Participants: 4926 pregnant women and 4130 live born infants. Interventions: 426 communities were randomised to five regimens in which pregnant women received daily supplements of folic acid, folic acid-iron, folic acid-iron-zinc, or multiple micronutrients all given with vitamin A, or vitamin A alone (control). Main outcome measures: Birth weight, length, and head and chest circumference assessed within 72 hours of birth. Low birth weight was defined Results: Supplementation with maternal folic acid alone had no effect on birth size. Folic acid-iron increased mean birth weight by 37 g (95% confidence interval −16 g to 90 g) and reduced the percentage of low birthweight babies (Conclusions: Antenatal folic acid-iron supplements modestly reduce the risk of low birth weight. Multiple micronutrients confer no additional benefit over folic acid-iron in reducing this risk. What is already known on this topic Deficiencies in micronutrients are common in women in developing countries and have been associated with low birth weight and preterm delivery What this study adds In rural Nepal maternal supplementation with folic acid-iron reduced the incidence of low birth weight by 16% A multiple micronutrient supplement of 14 micronutrients, including folic acid, iron, and zinc, reduced low birth weight by 14%, thus conferring no advantage over folic acid-iron