Nicotine and its influence on the female reproductive system.

Abstract

This brief review focuses on women and how their smoking can influence physiologic events from ovulation to birth, specifically the effects of nicotine, since effects of carbon monoxide in pregnancy have been reviewed extensively elsewhere. The nicotine alkaloid, which enters the body as a gas, has easy access to the brain stem and the central nervous system of the smoker, and it exerts effects on the nervous systems by activating nicotine cholinergic receptor sites. This interaction with the nervous systems has the consequence of altering adenohypophysial, neurohypophysial, adrenal, and catecholamine secretion patterns. These endocrine responses affect the continuum of events from ovulation to birth in the following ways: 1) alteration of H-P-O axis activity affecting ovulation or early tropic support preceding placental function; 2) alterations in oviductal or uterotubal junction activity leading to inappropriate entry of the blastocyst into the uterus; 3) alteration of catecholamine mediated changes in uterine or placental blood flow patterns; 4) fetal hypoxic episodes occurring in response to HbCO accumulation; and 5) inappropriate changes in fetal endocrine function.