[Metabolism of minerals and vitamin D in the pregnant woman and the fetus].

The mineral metabolism in the fetus and pregnant woman is described with reference to data from the medical literature and personal studies. As soon as the twenty-eighth week of gestation, a concentration gradient is established between mother and fetus for calcium, phosphorus and magnesium, with higher levels in the fetus. The vitamin D content of the fetus is dependent on that of the mother; in France, where food is not supplemented, vitamin D deficiency is common in mothers and neonates, especially during the winter and spring and in areas where sunlight is scarce. Vitamin D supplementation is therefore required during the last trimester of gestation.