Background.
Micronutrient deficiencies may contribute to a higher incidence of low birthweight (LBW). UNICEF/United Nations University/World Health Organization jointly proposed a formulation for a multiple micronutrient supplement for pregnant women, and several effectiveness trials were conducted to assess its impact.

Objective.
To evaluate the efficacy of prenatal multiple micronutrient supplementation for improving birth size, pregnancy outcome, and maternal micronutrient status in comparison with iron–folic acid supplementation.

Methods.
We carried out a cluster-randomized, controlled trial in Indramayu, Indonesia, involving 843 pregnant women. Of these, 432 received multiple micronutrients and 411 received iron–folic acid. Fieldworkers visited the women daily to observe supplement consumption and record fetal loss and mortality.
Results. The mean number of supplements consumed during pregnancy and 30 days postpartum was high (136 in the group receiving multiple micronutrients and 140 in the iron–folic acid group). The women consumed the supplements on average 5 days per week. Although there were no significant differences between the groups in the percentage of infants with LBW, there was a trend toward a lower incidence of LBW in the group receiving multiple micronutrients (6.3% vs. 7.3%), and the mean birthweight was 40 g higher in the group receiving multiple micronutrients than in the iron–folic acid group, although the difference was not significant. Among those who consumed 90 or more supplements during pregnancy, women taking multiple micronutrients had a 3.3% combined rate of miscarriage, stillbirth, or neonatal death, as compared with 6.9% for those taking iron–folic acid only (p < .049). The anemia rates in the two groups were similar after supplementation, even though the amount of iron in the multiple micronutrient supplement was half that in the iron–folic acid supplement. Serum retinol was higher in the group receiving multiple micronutrients.

Conclusions.
Multivitamin supplementation use among pregnant women is as effective as iron–folic acid in improving anemia status and appears to have other benefits for maternal and child nutritional status.