title: Neonatal hypermagnesemia: effect on parathyroid hormone and calcium homeostasis.
abstract: Twenty pre-eclamptic mothers treated with MgSO4 and their newborn infants were studied prospectively to determine the clinical and biochemical effects of hypermagnesemia. Maternal serum magnesium concentration rose to 4.4 mg/dl at delivery and was accompanied by a fall in maternal serum calcium concentration during labor. Neonatal serum Mg concentration remained elevated for the first 72 hours of life (mean at 72 hours = 3.0 mg/dl). Serum Mg concentration was higher in premature infants and in babies with birth asphyxia and/or hypotonia. Serum Ca concentration was higher and serum PTH was lower in hypermagnesemic study infants when compared to a retrospectively selected, matched froup of control infants. We speculate that elevated serum Mg values in these infants result in a shift of Ca from bone to plasma, and that elevated Mg and Ca concentrations further suppress neonatal parathyroid function.
mesh_terms: D002118:Calcium / Q000097:blood*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000097:blood*; D007234:Infant, Premature; D008274:Magnesium / Q000097:blood*; D008278:Magnesium Sulfate / Q000627:therapeutic use; D008431:Maternal-Fetal Exchange; D010281:Parathyroid Hormone / Q000097:blood*; D011225:Pre-Eclampsia / Q000188:drug therapy; D011247:Pregnancy; D011446:Prospective Studies
chemical_list: D010281:Parathyroid Hormone; D008278:Magnesium Sulfate; D008274:Magnesium; D002118:Calcium