Objective: To assess the effect of intravenous versus oral iron on hematologic indices and clinical outcomes for iron-deficiency anemia (IDA) in pregnancy. Study design: Searches in Ovid Medline, Embase, SCOPUS, Cochrane Database, and ClinicalTrials.gov identified randomized-controlled trials comparing intravenous to oral iron for treating IDA in pregnancy. Primary outcomes were maternal hematologic indices at delivery. Secondary outcomes were blood transfusion, cesarean delivery, neonatal outcomes, and medication reactions. Results: Of 15,637 studies, 20 randomized trials met inclusion criteria and were analyzed. Mean hemoglobin at delivery (9 studies: WMD 0.66 g/dL (95% confidence Interval 0.31 –1.02 g/dL)) was significantly higher after intravenous iron therapy. Intravenous iron was associated with higher birthweight (8 studies: WMD 58.25 g (95% CI: 5.57–110.94 g)) but no significant differences in blood transfusion, cesarean delivery, or neonatal hemoglobin. There were fewer medication reactions with intravenous iron (21 studies: RR 0.34% (95% CI: 0.20–0.57)). Conclusion: Intravenous iron therapy is associated with higher maternal hemoglobin at delivery with no difference in blood transfusion and fewer mild medication reactions.