Pregnancy and lactation are periods of high calcium requirement. Around 200-300 mg of calcium/day is either transferred via the placenta to the fetus or excreted in breast milk. The provision of this calcium is made by the physiological adaptations of calcium absorption, urinary calcium excretion, and maternal bone calcium turnover. So woman of child-bearing age will meet their own needs of calcium and those of their infants if they regularly consume adequate amounts of calcium (1,000mg/day). Additional calcium supplementation during pregnancy appears to have the greatest impact in women who chronically consume < 500 mg calcium /day.
Hypertensive disorders of pregnancy are more frequent in countries where the customary calcium intake is low. In such areas, World Health Organization recommended calcium supplementation as part of the antenatal care for the prevention of preeclampsia in pregnant women, particularly among those at higher risk of developing hypertension.

Keywords: Calcium metabolism; Pregnancy; Lactation; Preeclampsia; Osteoporosis.