Effect of vitamin D supplementation during pregnancy on maternal and neonatal outcomes: a systematic review and meta-analysis of randomized controlled trials

To assess the effects of vitamin D supplementation during pregnancy on obstetric outcomes and birth variables.Systematic review and meta-analysis of randomized controlled trials (RCTs).Not applicable.Pregnant women and neonates.PubMed and 5 other research databases were searched through March 2014 for RCTs evaluating vitamin D supplementation ± calcium/vitamins/ferrous sulfate vs. a control (placebo or active) during pregnancy.Measures were:...