Parathyroid Hormone Concentrations in Maternal and Fetal Blood and in Amniotic Fluid from Pregnant Rats

Abstract

Changes of parathyroid hormone (PTH) concentrations in maternal and fetal blood and in amniotic fluid throughout rat pregnancy were determined by radioimmunoassay. PTH levels in matemal blood increased during the last quarter of gestation, and seemed to play a significant role for maintaining maternal blood ionic calcium at a constant level. PTH levels in fetal blood and amniotic fluid remained mostly undetectable (less than 100 pg/ml).