The role of vitamin D deficiency in placental dysfunction: A systematic review.

Introduction: Vitamin D plays a critical role in pregnancy, supporting placental function via angiogenesis, immune regulation, and nutrient transport. Deficiency in vitamin D during gestation is associated with complications such as preeclampsia, intrauterine growth restriction (IUGR), and preterm birth. However, the mechanisms linking vitamin D deficiency to placental dysfunction remain inadequately understood, highlighting the need for systematic evaluation.