- Single micronutrient supplementation during pregnancy has few effects on maternal and neonatal outcomes.
Why this matters
- Almost 2 billion people around the world have vitamin and mineral deficiencies that adversely affect pregnancy and offspring.
- Compared with placebo:
- Vitamin A: no effect on maternal mortality, stillbirths.
- Zinc: no effect on risk for low birth weight (LBW), preeclampsia, preterm birth.
- Iron: reduced risk for maternal anemia by 47% (risk ratio [RR], 0.53; 95% CI, 0.43-0.65); no effect on perinatal mortality.
- Vitamin D: no effect on risk for small for gestational age or cesarean delivery (CD).
- Calcium: no effect on risk for LBW, stillbirths, preterm birth, CD. Calcium was tied to reduced risk for preeclampsia (RR, 0.45; 95% CI, 0.19-1.06).
- Multiple micronutrients: no effect on maternal mortality or perinatal mortality and decreased risk for LBW (RR, 0.85; 95% CI, 0.77-0.93) vs iron with or without folic acid.
- Lipid-based nutrient supplementation vs multiple micronutrients: no effect on risk for LBW, miscarriage, neonatal mortality.
- Systematic review, meta-analysis.
- Studies after 1995 on vitamin/mineral supplementation during pregnancy in healthy mothers of any age and parity in low- and middle-income countries (72 studies, 314 associated articles).
- Funding: Bill and Melinda Gates Foundation.
- Heterogeneity among studies.