[Serum levels of parathormone, calcium, magnesium and phosphorus in the perinatal period].

Two groups of newborns on different diets were studied: group A was given artificial milk, while group B was breast fed. Blood samples from the cord artery and vein were taken at birth and further blood samples after 1, 6, 12, 24, 48, 72, 96 and 168 hours. No baby underwent more than three blood samples. Calcium (Ca), magnesium (Mg), phosphorus (P) and parathormone (PTH) were measured in all samples. There was a rapid increase in PTH levels in all subjects in the first hours after birth. At 48th the babies in group A had significantly higher serum levels of P than the group B subjects, and their serum Ca and Mg levels were significantly lower. At 72th PTH serum levels were significantly higher in group A, while Ca and Mg levels were significantly higher in group B. In conclusion, the subjects demonstrated a normal secretion of PTH at birth, and the type of diet notably influenced the homeostasis of calcium in the perinatal period.