title: 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 micronutrient (MM) supplements with those of iron supplements during pregnancy on birth size.
  
  
  METHODS
  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.
  
  
  CONCLUSIONS
  These findings suggest that MM supplementation during pregnancy does not lead to greater infant birth size than does iron-only supplementation.
authors.affiliation: Department of International Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA. uramakr@sph.emory.edu
authors.forename: Usha
authors.initials: U
authors.lastname: Ramakrishnan
authors.forename: Teresa
authors.initials: T
authors.lastname: González-Cossío
authors.forename: Lynnette M
authors.initials: LM
authors.lastname: Neufeld
authors.forename: Juan
authors.initials: J
authors.lastname: Rivera
authors.forename: Reynaldo
authors.initials: R
authors.lastname: Martorell
mesh_terms: D000328:Adult; D001724:Birth Weight / Q000187:drug effects*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007501:Iron / Q000008:administration & dosage*; D008800:Mexico; D018977:Micronutrients / Q000008:administration & dosage*; D018673:Nutrition Policy; D011247:Pregnancy; D011295:Prenatal Care; D039401:Prenatal Nutritional Physiological Phenomena; D012423:Rural Health
chemical_list: D018977:Micronutrients; D007501:Iron