Vitamin D in the Newborn, Part I: Assessment of Status and Deficiency Risk Factors

Abstract

Since 2008, the American Academy of Pediatrics (AAP) has published three documents related to vitamin D requirements of term and preterm infants. The need for developing and updating such guidelines emphasizes the importance of vitamin D not only as an essential element of bone health but also as a nutrient and prohormone that plays an increasingly recognized role in many other organ systems. In this review, we describe: (1) the main circulating metabolites of vitamin D; (2) the significance of their respective blood concentrations during the assessment of vitamin D status; and (3) the factors that influence vitamin D status at birth and the risk factors for neonatal vitamin D deficiency. In a separate article, we discuss the evidence for current vitamin D dietary recommendations in term neonates and delineate the role of vitamin D deficiency in the pathogenesis of osteopenia of prematurity.