Effect of Treatment with Vitamin D on Maternal and Neonatal Indices in Pregnant Women with Hypocalcemia: A Randomized Controlled Trial

Background The impact of concomitant vitamin D deficiency and maternal hypocalcemia on fetal growth has is not clear. The aim of this study was to determine the effect of treatment with vitamin D on maternal and neonatal indices in pregnant women with hypocalcemia. Materials and Methods This clinical trial was conducted on 110 pregnant women (22-26 weeks of gestational age) with simultaneous mild hypocalcemia (8 < serum calcium< 8.5 mg/dL) and vitamin D deficiency (25 (OH) D< 75 nmol/L).  The study subjects were randomly allocated to intervention (n=55) and control (n=55) groups. In the control group, the subjects were given daily prenatal capsule until delivery. In the intervention group, the subjects were given 50,000 Units vitamin D weekly for eight weeks in addition to prenatal capsules until delivery similar to the control group. At delivery, maternal calcium and 25 (OH) D level and neonatal indices (weight, height, and head circumference) were measured and compared between the groups. Results At delivery, mean maternal vitamin D level was 97.5±23.4 nmol/L in the intervention group and 48.9±17.2 nmol/L in the control group, respectively (P<0.001). Mean maternal calcium level in the intervention group was higher than the control group (9.0±0.6 mg/dl vs. 8.8±0.5 mg/dl) but the difference was not statistically significant (P> 0.05). Mean neonatal weight, height, and head circumference were not significantly different between the two groups (P> 0.05). Conclusion In pregnant women with mild hypocalcemia, treatment with vitamin D would not have effect on mean serum calcium and neonatal indices.