Perinatal metabolism of vitamin D.
During pregnancy, maternal serum concentrations of 25-hydroxyvitamin D, the circulating form of vitamin D, correlate with dietary vitamin D intake. Maternal serum concentrations of 1,25-dihydroxyvitamin D, the hormonal circulating and active form of vitamin D, are elevated during pregnancy; 1,25-dihydroxyvitamin D is synthesized mainly by the decidual cells of the placenta and allows for increased calcium absorption. The fetus is entirely dependent on the mother for its supply of 25-hydroxyvitamin D, which is believed to cross the placenta. Hypocalcemia and increased parathyroid hormone secretion induce synthesis of 1,25-dihydroxyvitamin D after birth in both full-term and preterm neonates. Nevertheless, serum concentrations of 25-hydroxyvitamin D are a rate-limiting factor in the synthesis of 1,25-dihydroxyvitamin D. In vitamin D-replete infants, circulating 1,25-dihydroxyvitamin D concentrations are higher than those observed in older infants. In countries where dairy products are not routinely supplemented with vitamin D, maternal vitamin D supplementation during pregnancy is necessary. However, there is no indication for the use of pharmacologic doses of vitamin D or its metabolites in the perinatal period.
Salle
B L
BL
Department of Neonatology and Human's Nutrition Center, Hôpital Edouard Herriot, Lyon, France. salle@univ-lyon1.fr
Delvin
E E
EE
Lapillonne
A
A
Bishop
N J
NJ
Glorieux
F H
FH
D019587:Dietary Supplements; D005260:Female; D005333:Fetus / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn / Q000378:metabolism*; D007234:Infant, Premature / Q000378:metabolism; D009747:Nutritional Physiological Phenomena; D018743:Perinatal Care; D011247:Pregnancy / Q000378:metabolism*; D014807:Vitamin D / Q000378:metabolism*
D014807:Vitamin D