Features of vitamin D metabolism during pregnancy

Vitamin D plays an important role in the regulation of the «mother-placenta-fetus» system, participating in ensuring normal growth and development of the fetus, reducing the risks of hypocalcemia, muscle cramps, respiratory infections in childhood. To date, the existence of more than 50 metabolites of vitamin D has been established, of which the most studied are total 25-hydroxyvitamin D (25 (OH) D) and 1,25-dihydroxyvitamin D (1,25 (OH) 2D), which is due, first of all, to their importance for the endocrine regulation of calcium-phosphorus metabolism. The level of 25 (OH) D in the blood is an optimal, but not perfect marker of vitamin D status, and does not reflect the numerous effects of its metabolites. Taking into account the special metabolic adaptation of a woman’s body during gestation, the analysis of quantitative changes in various vitamin D metabolites is of particular relevance. This review summarizes the available data on the characteristics of vitamin D metabolism outside gestation and during pregnancy.