Effect of nicotine upon uterine blood flow in the pregnant rhesus monkey.

Acute effects of nicotine upon the uterine blood flow, blood pressure, maternal and fetal acid-base state, and oxygenation were determined in eight pregnant rhesus monkeys near term. Nicotine was infused intravenously to the mother in a dose of 100 microgram/kg per body weight/minute over 20 minutes. The flow rate was measured with the use of the electromagnetic flowmeter. Significant decrease in the uterine arterial blood flow rate, as much as 38% of the control value, was observed during the first 15 minutes of the infusion while aortic pressure increased by 14%. Acidosis and hypoxia resulted in the fetus. Considered together with our previously reported data, the present investigation appears to indicate that the adverse effects of nicotine to the fetus are due to the combined effects of the reduced uterine blood flow and the transmitted nicotine to the fetus.