This study will investigate effects of reproductive hormones by temporarily stopping the menstrual cycle with leuprolide acetate and then giving, in sequence, the menstrual cycle hormones progesterone and estrogen. Tests (such as brain imaging or stress testing, etc.) will be performed during the different hormonal conditions (low estrogen and progesterone, progesterone add-back, estrogen add-back). The results of these studies will be compared between women without PMS and women with PMS (see also protocol 90-M-0088).