Antenatal Intravenous Iron Therapy in Anemic Pregnancies: Associations with Obstetric Patient Blood Management and Neonatal Outcomes

Background: Anemia in pregnancy is associated with increased maternal and neonatal morbidity, most commonly due to iron deficiency. The effect of antenatal IV iron therapy on obstetric patient blood management (PBM) and neonatal outcomes remains uncertain. Objective: To evaluate whether antenatal IV iron therapy in pregnancy is associated with improved obstetric PBM, specifically reduced RBC transfusion and postpartum IV iron use, and improved neonatal outcomes. Methods: In this multicenter retrospective study, 851 pregnant women with IDA were included (490 received antenatal IV iron; 361 controls). Multivariable logistic regression adjusted for clinically relevant confounders assessed maternal and neonatal outcomes. A propensity score-adjusted sensitivity analysis addressed baseline differences. Results: The median gestational age at infusion was 35 weeks (range 30–37). The treated group had a higher obstetric risk profile, lower baseline hemoglobin at 9.2 (range 5.5–12.7) vs. 9.8 (range 7.9–12) g/dL, and more frequent oral iron use (30–100 mg/day; 66.1% vs. 53.7%; p < 0.001). Gestational age at delivery, estimated blood loss, and postpartum hemorrhage were similar between groups. After adjustment, antenatal IV iron therapy was associated with 56% and 72% lower odds of RBC transfusion and postpartum IV iron use, respectively; the reduced odds of blood transfusion remained significant after propensity score adjustment (aOR 0.42, 95%CI 0.16–0.99). A significant interaction with baseline hemoglobin was observed, with benefit mainly in women with a lower baseline. Neonatal outcomes were similar between groups, although NICU/high-dependency admission and phototherapy for jaundice were less frequent among neonates of treated women. Conclusions: Antenatal IV iron therapy was associated with reduced transfusion exposure and lower postpartum IV iron requirements, despite lower baseline Hb values. These findings support antenatal hematologic optimization in obstetric PBM and highlight the need for further studies to clarify potential neonatal benefits.