Folic acid and iron supplementation in pregnancy
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Effectiveness of Iron and Folic Acid Supplementation in Pregnancy
Daily supplementation with iron or iron plus folic acid during pregnancy is effective in increasing maternal hemoglobin levels and reducing the risk of maternal anemia and iron deficiency at term Peña-Rosas2009Finkelstein2024Peña-Rosas2006+2 MORE. Both daily and intermittent regimens are effective, with no significant difference in preventing anemia at term, though daily regimens may slightly increase hemoglobin levels more than intermittent ones Peña-Rosas2009Peña-Rosas2006Chillo2025. Supplementation also probably reduces the risk of iron-deficiency anemia and may lower the likelihood of low birthweight infants, though the evidence for improvements in other infant outcomes, such as preterm birth or neonatal death, is less certain or shows little to no difference Finkelstein2024Peña-Rosas2015Peña-Rosas2012.
Safety and Side Effects of Iron and Folic Acid Supplementation
Daily iron or iron plus folic acid supplementation is associated with more frequent side effects, such as gastrointestinal discomfort, and a higher risk of haemoconcentration (very high hemoglobin levels), especially with daily regimens Peña-Rosas2009Peña-Rosas2006Peña-Rosas2015+2 MORE. Intermittent regimens tend to have fewer side effects and better adherence among pregnant women . The clinical significance of haemoconcentration during pregnancy remains uncertain, and there is no clear evidence that iron supplementation increases the risk of malaria in endemic areas Peña-Rosas2009Peña-Rosas2015Peña-Rosas2012.
Adherence to Iron and Folic Acid Supplementation
Adherence to iron and folic acid supplementation is crucial for its effectiveness in preventing anemia during pregnancy Saragih2021Birhanu2018Seidu2024. Factors that improve adherence include early initiation of antenatal care, frequent antenatal visits, fewer tablets per visit, urban residence, prior history of anemia, and good knowledge about anemia and supplementation Saragih2021Birhanu2018Seidu2024. Education on the benefits and management of side effects, as well as support from family members, can further enhance adherence Sartika2024Seidu2024. Studies show that adherence rates vary widely, but knowledge and early engagement with antenatal care are consistently linked to better compliance Saragih2021Birhanu2018Seidu2024.
Impact on Maternal and Infant Outcomes
Iron and folic acid supplementation during pregnancy is strongly associated with reduced maternal anemia, but its effect on infant anemia is less clear Finkelstein2024Peña-Rosas2015Peña-Rosas2012+1 MORE. While supplementation may slightly increase infant birthweight, there is little to no difference in rates of preterm birth, neonatal death, or congenital anomalies Finkelstein2024Peña-Rosas2015Peña-Rosas2012. The benefits for infant health may be indirect, as maternal anemia is a risk factor for infant anemia, highlighting the importance of monitoring and supporting maternal health throughout pregnancy .
Conclusion
Iron and folic acid supplementation during pregnancy is effective in preventing maternal anemia and iron deficiency, with both daily and intermittent regimens showing benefits. Side effects are more common with daily regimens, but intermittent dosing may improve adherence. While the impact on infant outcomes is less pronounced, supporting adherence through education, early antenatal care, and family involvement is key to maximizing the benefits of supplementation for maternal and infant health.
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