Multiple micronutrient supplementation during pregnancy does not lead to greater infant birth size than does iron-only supplementation: a randomized controlled trial in a semirural community in Mexico.
Abstract
BACKGROUND Little is known about the benefits of prenatal multivitamin and mineral supplements in reducing low birth weight. OBJECTIVE We conducted a randomized, double-blind clinical trial in semirural Mexico to compare the effects of multiple mic...
BACKGROUND Little is known about the benefits of prenatal multivitamin and mineral supplements in reducing low birth weight. OBJECTIVE We conducted a randomized, double-blind clinical trial in semirural Mexico to compare the effects of multiple micronutrient (MM) supplements with those of iron supplements during pregnancy on birth size. DESIGN Pregnant women (n = 873) were recruited before 13 wk of gestation and received supplements 6 d/wk at home, as well as routine antenatal care, until delivery. Both supplements contained 60 mg Fe, but the MM group also received 1-1.5 times the recommended dietary allowances of several micronutrients. RESULTS At recruitment, the women in the 2 groups were not significantly different in age, parity, economic status, height, or hemoglobin concentration but differed significantly in marital status (4.6% and 2.0% of women in the MM and iron-only groups, respectively, were single mothers) and mean (+/- SD) body mass index (in kg/m(2); 24.6 +/- 4.3 and 23.8 +/- 3.9 in the iron-only and MM groups, respectively). Losses to follow-up (25%) and compliance (95%) did not differ significantly between the groups. In intent-to-treat analyses (MM group: n = 323; iron-only group: n = 322), mean (+/- SD) birth weight (2.981 +/- 0.391 and 2.977 +/- 0.393 kg in the MM and iron-only groups, respectively) and birth length (48.61 +/- 1.82 and 48.66 +/- 1.83 cm in the MM and iron-only groups, respectively) did not differ significantly between the groups. CONCLUSION These findings suggest that MM supplementation during pregnancy does not lead to greater infant birth size than does iron-only supplementation.