Effect of vitamin D supplementation during pregnancy on the neonatal skeletal growth in the rat.

In rats on normal intakes of calcium, phosphorus and vitamin D3, 3,000 and 7,500 IU of vitamin D3 were injected on the 10th day of pregnancy and the pups were investigated for the skeletal growth on 28th day of age. Compared to controls, the pups in the supplemented groups showed significantly greater dry weight and ash weight of the tibiae. However, the ash weight/dry bone weight ratios in the supplemented groups were not different from controls. Histological examination of the upper ends of decalcified tibiae and plasma calcium estimations revealed no abnormality in any group. The results suggest that vitamin D3 supplementation in pregnancy enhances the skeletal growth of the pups which involves both the organic and inorganic components.