[Vitamin D and pregnancy].

Vitamin D plays a key role in calcium-phosphorus homeostasis and bone metabolism, but it is also involved in numerous others tissues. Vitamin D deficiency among pregnant women is frequent in many populations over the world. It is associated with an increased risk of preeclampsia, gestational diabetes mellitus, and caesarean section. Consequences in newborns are low birth weight, neonatal rickets, a risk of neonatal hypocalcemia, asthma and/or type 1 diabetes. Therefore, prevention of vitamin D deficiency among pregnant women is essential. The currently recommended supplementation amount of vitamin D is not sufficient to maintain a value of 25 hydroxy vitamin D above 30 ng/ml, during pregnancy. Randomized controlled trials during pregnancy are necessary to evaluate the amount of vitamin D sufficient to avoid the consequences of vitamin D deficiency.