Abstract
There is increasing interest in vitamin D nutrition during pregnancy because of widespread reports of a high prevalence of low vitamin D status in pregnant women. While vitamin D is important for calcium and phosphorus homeostasis and for bone health, it also plays important roles in many other physiologic functions in the body. Consistent with the expanded role of vitamin D, recent observational studies have demonstrated that low vitamin D status in pregnancy is associated with multiple potential adverse maternal, fetal, and infant outcomes and contributes to low vitamin D status in infants at birth. Therefore, an overview of the current understanding of vitamin D nutrition in pregnancy and a review of the results of studies to optimize vitamin D status during pregnancy and in the offspring is of public health importance and timely.