A Comparison Between Maternal and Neonatal Serum Level of Vitamin D and Its Relationship with Anthropometric Neonatal Factors

Background & Objective: The aims of present study were to compare the vitamin D concentration in pregnant women and the umbilical cord blood while investigating for a relationship between its level and anthropometric neonatal factors (i.e. birth weight, birth length, and head circumference). Materials & Methods: The study was performed as a descriptive cross-sectional study on pregnant women who were admitted to the labor ward for delivery. Serum level of 25-hydroxyvitamin D [25(OH) D], was measured and compared in women and the umbilical cord blood. The relationship between 25(OH) D levels and anthropometric neonatal factors including birth weight, birth length and head circumference was evaluated. Results: A total of 106 pregnant women (53 Iranians and 53 Afghan refugees’ women) were evaluated. There was a significant correlation between maternal serum level of 25(OH) D and that of their neonates, both in Iranians and Afghans considering gestational age as a confounding factor (R=0.62, P=0.000). Maternal and neonatal 25(OH) D levels were significantly higher in Iranians than Afghans (27.2±11.5 ng/mL VS 21.9±12.7 ng/mL, P=0.026 and 26.5±11.2 VS 17.3±11.4, P=0.000) respectively. However, neonatal weight and head circumference (HC), were not different in Iranians and Afghans except for neonatal height which was higher in Afghans (P=0.015) irrespective of lower amount of neonatal 25(OH) D levels. The mean cord levels of vitamin D in boys and girls did not show a significant difference. There was no significant correlation between 25(OH) D serum level and pregnant women’s level of education, pre-labor rupture of membranes (PROM), past medical history (PMH), taking supplements and smoking. Conclusion: Maternal and neonatal 25(OH) D levels did not influence neonatal anthropometry.