Maternal 25OHD Research Articles

Human perinatal vitamin D metabolism I: 25-Hydroxyvitamin D in maternal and cord blood

A highly significant correlation was observed in the concentrations of 25-hydroxyvitamin D (25-OHD) in mother's serum and in the mixed arterial-venous cord serum of their respective infants, regardless of whether the infant was born at term, prematurely, or as a twin. At maternal concentrations of 15 to 30 ng. per milliliter, infant levels averaged 80±5 per cent of matemal levels whereas, at matemal concentrations below 15 ng. per milliliter, infant levels averaged 108±8 per cent. Infant and maternal-infant differences were not correlated with gestation and only weakly with birth weight. Apparent influences on maternal 25-OHD concentrations were race and season. These data are consistent with passive or facilitative placental transfer of 25-OHD and identify maternal stores as the critical factor determining infant levels at birth.