Plasma 1,25-dihydroxyvitamin D concentrations in cords, newborns, infants, and children

Abstract
Plasma 1,25-dihydroxyvitamin D [1,25-(OH)2-D] was measured in cord serum, newborns, infants, and children. The mean for the values obtained from the six cords was significantly higher than the mean for the older children (6–15 years). The mean for the six newborns (0–1 week) was significantly higher than that for the older children. The mean for the nine infants (1 week-6 months) and the 14 younger children (6 months-6 years) was significantly higher than that for older children. The present study suggests that the perinatal period is associated with a marked increase in 1,25-(OH)2-D.