The role of vitamin D physiology in regulating calcium and bone metabolism in mother and child

During pregnancy and lactation, female physiology adapts to enable the mother to meet her own mineral needs as well as those of the fetus and infant. These adaptations in maternal mineral and bone metabolism appear to be invoked independent of maternal vitamin D physiology, while fetal mineral metabolism and skeletal development appear to be protected from vitamin D deficiency and genetic disorders of vitamin D physiology. Conversely, disruptions in vitamin D physiology during the postnatal period can lead to impaired calcium and phosphorus absorption, hypocalcemia, hypophosphatemia, secondary hyperparathyroidism, and rickets or osteomalacia. This review discusses key data from both animal models and human studies to address our current knowledge on the role of vitamin D and 1,25(OH)2D in mineral and bone metabolism during pregnancy, lactation, fetal, and postnatal periods. Brief remarks are also made concerning the evidence for potential nonskeletal roles of vitamin D and 1,25(OH)2D during these time periods.