Human Maternal and Fetal Insulin Response to Arginine

Abstract
Maternal and fetal insulin response to arginine was examined by infusion of arginine to pregnant women during delivery of their fetuses or to newborn infants directly. Nonpregnant adult subjects were studied as controls. A positive correlation between plasma immunoreactive insulin concentration and plasma arginine concentration was found in the control subjects. The pregnant women at 13 to 18 weeks' gestation had an attenuated insulin response to arginine, whereas the responses of the women during labor and delivery at term were more variable. The fetuses in utero had no significant plasma insulin rise to maternal infused arginine. The newborn infant, however, had attenuated though significant insulin response to intravenous arginine infusion.