The effect of iron supplementation on birth outcome in mothers with high hemoglobin: a randomized double-blind clinical trial study

Abstract Background: Although Iron supplementation is a chief component of prenatal care to prevent anemia in pregnant women, Extreme maternal iron status may adversely affect pregnancy outcome. The aim of this study was to examine the effect of iron supplementation on birth outcomes among pregnant women with high hemoglobin. Methods: In a randomized, double-blind, placebo-controlled trial,189 women who had a hemoglobin concentration more than 13.2 g/dl and a serum Ferritin level higher than 15 μg/l between the 16th and 20th weeks of pregnancy took either one 50 mg tablet of ferrous sulfate daily or placebo during their pregnancies. The data obtained from 13 pregnant women were not used in final analysis for different reasons. After birth, the birth weight, head circumference and birth height in each group were measured and compared, and also two groups compared due to risk of neonatal jaundice. Results: The mean of maternal age and pre- pregnancy BMI was 26.11±5.13, 23.9±2.32, respectively. There were no statistically significant differences between the two groups with respect to birth weight and height, but the difference in head circumference was significant (P=0.003). Also, the risk of neonatal jaundice in intervention group was more than that in control (P=0.005). Conclusion: Iron supplementation in mothers with high hemoglobin did not increase the risk of maternal anemia or low birth weight, but the supplementation increased the risk of jaundice in newborns. It was an interesting finding that the birth head circumference was larger in the non-supplement group than that in the intervention group. Key words: Pregnancy, ferrous sulfate, Birth Weight, Head Circumference, Neonatal jaundice. Clinical trial registration: IRCT2013020612383N1, Registered 27.06.2014