Vitamin D Status in Early Preterm Infants

ABSTRACT

PURPOSE: Vitamin D deficiency is still common in pregnant women and infants, especially preterm infants. This study evaluated the prevalence, characteristics, and prenatal and postnatal complications associated with vitamin D deficiency in preterm infants. METHODS: Preterm infants (gestational age of <32 weeks, delivered between January 2014 and December 2014) were divided into two groups according to umbilical cord blood 25-hydroxyvitamin D concentrations (deficiency group, <20 ng/mL; non-deficiency group, ≥20 ng/mL), and associated factors were evaluated. RESULTS: The mean concentration of 25-hydroxyvitamin D in the preterm infants was 14.3±9.7 ng/mL. 80% (78 out of 98) of subjects had vitamin D deficiency (<20 ng/mL), and 45% (44 out of 98) of preterm infants had a severe vitamin D deficiency (<10 ng/mL). No seasonal variation was observed in 25-hydroxyvitamin D concentration. Mean gestational age and birth weight were lower in the deficiency group. The serum calcium and alkaline phosphatase (ALP) concentrations, which reflect bone metabolism, were significantly different between the two groups, but not the serum phosphorous concentrations. Maternal prenatal complications and infant complications were not significantly different between the two groups. CONCLUSION: The prevalence of vitamin D deficiency is high, and it is a persistent problem among Korean mothers and their newborn infants, especially preterm infants. Thus, it is important to prevent vitamin D deficiency by early detection of the deficiency and supplementation of vitamin D.