Multiple micronutrient supplementation (MMS) in pregnancy reduces the risk of low birthweight and improves other maternal and infant outcomes; however, the role of timing of initiation and supplement adherence in the effectiveness of MMS remains unclear. As the first individual participant data meta-analysis that examines the timing of initiation and adherence of MMS, our study finds that higher MMS adherence and a greater number of tablets taken were generally associated with more positive birth outcomes.
