Abstract
Venous blood was obtained from 100 consecutive and unselected Saudi Arabian mothers and their neonates within 48 h after delivery. This study revealed that vitamin D deficiency is very prevalent during pregnancy in Saudi Arabia. It also showed that asymptomatic hypocalcemia in full term babies is far commoner than is generally appreciated. It is considered that vitamin D deficiency is primarily due to lack of exposure to sunlight. Encouragement to obtain sunlight exposure and fortification of food are the only alternative measures.