intravenous vs oral Iron for treating Iron deficiency anaemia in pregnancy

Intravenous vs Oral Iron for Treating Iron Deficiency Anaemia in Pregnancy

Overview

• Study Design:
  • updated systematic review and meta-analysis of 29 randomized clinical trials (RCTs) comparing intravenous (IV) vs oral iron for iron deficiency anaemia (IDA) in pregnancy, encompassing 11,771 unique participants
• Core Objective:
  • evaluate the comparative association of IV vs oral iron therapy with maternal and neonatal hematologic outcomes, transfusion rates, and medication adverse events

Key Findings

• Maternal Hematologic Indices:
  • IV iron was associated with significantly higher mean maternal hemoglobin at delivery admission (WMD 0.59 g/dL; 95% CI 0.31–0.87) and 4–6 weeks post-treatment (WMD 0.64 g/dL; 95% CI 0.43–0.85)
  • IV iron was associated with higher maternal ferritin at delivery (WMD 50.93 ng/mL; 95% CI 33.56–68.29) and 4–6 weeks post-treatment (WMD 77.33 ng/mL; 95% CI 67.12–87.53)
  • improvements in maternal hemoglobin were most marked in individuals with pretreatment hemoglobin $\le$9.0 g/dL (WMD 0.70 g/dL; 95% CI 0.19–1.21)
• Blood Transfusion Risk:
  • IV iron therapy was associated with a 37% overall reduction in the rate of blood transfusion during delivery hospitalization (RR 0.63; 95% CI 0.49–0.82)
  • the reduction in transfusion risk was particularly pronounced among patients with pretreatment hemoglobin <=9.0 g/dL (RR 0.58; 95% CI 0.45–0.76)
• Neonatal Outcomes:
  • IV iron was associated with significantly higher neonatal ferritin levels at delivery compared to oral iron (WMD 21.38 ng/mL; 95% CI 5.50–37.25)
  • no statistically significant differences were observed for neonatal hemoglobin, birth weight, gestational age at delivery, or cesarean delivery rates
• Adverse Effects & Safety:
  • IV iron was associated with a 44% lower overall rate of mild adverse effects (RR 0.56; 95% CI 0.41–0.76), primarily driven by an 89% reduction in gastrointestinal side effects (RR 0.11; 95% CI 0.05–0.23)
  • no serious adverse events (anaphylaxis or death) were reported across either treatment group

Clinical Practice & Public Health Takeaways

• Re-evaluating First-Line Guidelines:
  • current clinical guidelines recommending oral iron as first-line therapy may need reconsideration given the clear benefits of IV iron in improving hematologic parameters and reducing blood transfusion requirements
• Reduction of Maternal Morbidity:
  • reducing delivery blood transfusions lowers the risk of maternal alloimmunization and serious maternal morbidity
• Long-Term Neonatal Benefits:
  • enhancement of neonatal ferritin stores at birth via IV maternal iron administration may protect against long-term childhood growth deficits and neurodevelopmental impairment

Referrence:

1. Sales SK, Rajprohat S, Simon L, et al. Intravenous vs Oral Iron for Treating Iron Deficiency Anemia in Pregnancy: A Systematic Review and Meta-Analysis. JAMA Netw Open. Published online September 23, 2026;9(9):e2630657.