Vitamin D status during pregnancy: maternal, fetal, and postnatal outcomes

Purpose of review To consider evidence from recent studies linking maternal vitamin D status during pregnancy with maternal, fetal, and postnatal outcomes. Recent findings Several studies have demonstrated an association between poor maternal vitamin D status and severe preeclampsia, though results are inconsistent and cannot be generalized to nonsevere preeclampsia. Pregnant women with gestational diabetes, intrahepatic cholestasis of pregnancy, and periodontal disease had lower vitamin D status at mid-gestation or delivery compared with controls. Maternal vitamin D status early in pregnancy was associated with risk of low birth weight and small-for-gestational age infants in one study, whereas another study found this relation only among white women. Polymorphisms in the vitamin D receptor gene may contribute to vitamin D-related disparities in fetal growth. Evidence from recent studies suggests an early prenatal influence of maternal vitamin D status on fetal skeletal development, with lasting postnatal effects. Cord blood vitamin D status was associated with tolerogenic immune regulation and fewer respiratory infections in the newborn. Summary Recent evidence supports a role of maternal vitamin D status, particularly early in pregnancy, in modulating the risk of pregnancy complications and in sustaining fetal growth, bone development, and immune maturation.