PMS is a condition characterized by changes in mood and behavior that occur during the second phase of the normal menstrual cycle (luteal phase). This study will investigate possible hormonal causes of PMS by temporarily stopping the menstrual cycle with leuprolide acetate and then giving, in sequence, the menstrual cycle hormones progesterone and estrogen. The results of these hormonal studies will be compared between women with PMS and healthy volunteers without PMS (see also protocol 92-M-0174).