Effects of neonatal exposure to progesterone in sexual behavior of male and female rats.

HULL, E. Effects o f neonatal exposure to progesterone on sexual behavior o f male and female rats. PHYSIOL. BEHAV. 26(3) 401--405, 1981 .--Lactating females received daffy injections of progesterone or off, and their offspring were gonadectomized in adulthood and tested for both musculine and feminine sexual behavior elicited by estrogen, progesterone, and testosterone regimens. Male offspring of progesterone treated females exhibited significant impairment of masculine behavior elicited by both estrogen and testosterone. Latency and frequency of mounts and intromissions of those males which did engage in sexual behavior were not significantly different for the two groups. There were nonsignificant trends toward demasculinization of progesterone treated females and feminization of progesterone treated males. Progesterone administered to estrogen primed males failed to facilitate lordosis. There were no progesterone related differences in body weight at any time nor in testis or accessory organ weights of males. The results of this experiment confirm our previous finding of reduced sexual competence of intact male rats exposed neonatally to moderately increased levels of progesterone, and indicate that this effect is not the result of diminished adult hormone levels. Neonatal exposure to progesterone appears to have minimal or no effect on feminine sexual behavior of rats.