The effect of graded doses of vitamin D on the serum calcium and phosphorus levels; the influences of varying doses of vitamin D on the incidence of hypocalcemia during the first week of life.

It has been established by several investigators that infants fed cow's milk formulae during the first week of life tend to develop lower serum calcium and higher phosphorus levels than infants fed breast milk. 1-4 Vitamin D administered in physiologic doses, i. e., 600 U. S. P. units per day during the first week of life, aggravates this tendency.5 Hypocalcemia has also been observed on the first day of life before any feedings have been given. 6-10 Since hypocalcemia of varying etiology has been successfully treated with large doses of vitamin D, 11-17 we studied the effect of graded doses of vitamin D on the serum calcium and phosphorus levels and the incidence of hypocalcemia occurring during the first week of life. Patient Material and Methods All infants studied were normal newborn infants who received a processed milk formula of isocaloric nature, containing 77 mg. of calcium and 51 mg.