human chorionic somatomammotropin (HCS), a hormone produced by the syncytiotrophoblast during pregnancy. It regulates carbohydrate and protein metabolism of the mother to ensure delivery to the fetus of glucose for energy and protein for fetal growth. HCS, an insulin antagonist, also may have a diabetogenic effect in the mother, who therefore may have an increased blood glucose level. Also called chorionic growth hormone-prolactin, human placental lactogen.
