Estrous cyclicity in rats fed an ethanol diet for four months.

This study is designed for better understanding the effect of chronic ethanol treatment on ovarian function in sexually mature rats by assessing the estrous cycle. Rats were fed the following diets for 17 weeks: a liquid diet containing 5% (w/v) ethanol, a liquid diet without ethanol (pair-fed) or laboratory chow and water ad lib. Estrous cycles were determined throughout the 17 weeks and the rats were necropsied at proestrus and metestrus. Ethanol-fed rats had significantly more irregular estrous cycles than did controls, and the duration of an estrous cycle in the ethanol-treated rats was statistically longer than that of controls. However, ovarian and uterine weights and ovarian and vaginal morphology of ethanol-fed rats were similar to those of controls.