Vitamin D levels are of vital importance during pregnancy, as vitamin D deficiency can lead to an increased risk of preeclampsia, gestational diabetes, impaired immune system and low birth weight of the newborn.
Vitamin D has multiple and vital physiological functions such as regulation of metabolism, maintenance of bones and teeth, involvement in the proper functioning of the immune system and participation in the process of insulin secretion.
According to a Cochrane review, supplementation of pregnant women with vitamin D alone is likely to reduce the risk of pre-eclampsia, gestational diabetes and low birth weight, and may reduce the risk of severe postpartum hemorrhage. It is not well known whether it may influence the risk of preterm delivery at less than 37 weeks' gestation.