Progesterone and sexual behavior in males.

Previous investigations into the effects of progestins on copulatory behavior have suggested that progesterone inhibits the expression of androgen-dependent sexual behaviors in males. However, virtually all of those studies utilized pharmacological dosages of progesterone. Such experiments, although essential for understanding the behavioral effects of progesterone, yield little insight into the function of endogenous progesterone in masculine sexual responses. In this brief review, attention is focused on the role of physiological levels progesterone in copulatory behavior in male reptiles and mammals. Efforts are made to promote a reevaluation of the behavioral effects of progestins in males, similar to ongoing studies which are reexamining neural mechanisms involved in progestin-mediated reproductive behavior in the female.