Vitamin D deficiency (vdd) is a public health problem. 50% of the world population have inadequate levels of vitamin D. Vitamin D is necessary for the absorption and metabolism of calcium and phosphorus. More than 90% of pregnant women had vitamin D insufficiency. According to the vitamin D council, pregnancy is a known risk factor for vitamin D deficiency. Vitamin D deficiency during pregnancy increases the risk of pre‐eclampsia, gestational diabetes, preterm birth, and low birthweight. Pregnant mothers who are deficient in vitamin D should be treated with cholecalciferol or ergocalciferol. Supplementing pregnant women with vitamin D reduces the risk of pre-eclampsia, gestational diabetes, low birthweight and the risk of severe postpartum haemorrhage.