• ELIGIBILITY CRITERIA:

Volunteers participating in this study will be women between the ages of 18 and 55 years, not pregnant, in good medical health, medication free, and who have no history of menstrual-related mood or behavioral disturbances. The absence of menstrual-related mood disorders will be prospectively confirmed during a two month period prior to the study entry when subjects will complete daily visual analogue rating scales monitoring both mood and behavior as outlined in NIMH protocol # 81-M-0126. Additionally, we will recruit a subsample of 20 asymptomatic women who will meet all inclusion and exclusion criteria in this protocol except they will have a history of a past major depressive episode.

The Structured Clinical Interview for DSM-IV will be administered to controls prior to study entry. Any control with a current or past axis I psychiatric diagnosis will be excluded from participating in this protocol (except in the subgroup of asymptomatic women with a past major depressive episode who participate in this protocol).

Subjects taking birth control pills or diuretics will be excluded from the study, as will patients taking psychotropic agents (e.g., lithium carbonate, tricyclic antidepressants). All subjects will be required to use non-hormonal forms of birth control (e.g., barrier methods) to avoid pregnancy during this study.

The following conditions will constitute contraindications to treatment with hormonal therapy and will preclude a subject's participation in this protocol: 1) history consistent with endometriosis; 2) diagnosis of ill-defined, obscure pelvic lesions, particularly undiagnosed ovarian enlargement; 3) hepatic disease as manifested by abnormal liver function tests; 4) history of mammary carcinoma; 5) history of pulmonary embolism or phlebothrombosis; 6) undiagnosed vaginal bleeding; 7) porphyria; 8) diabetes mellitus; 9) history of malignant melanoma; 10) cholecystitis or pancreatitis; 11) cardiovascular or renal disease; 12) pregnancy; and 13) a past or current Axis I psychiatric illness (with the exception of those women with a past major depression who will be studied in this protocol). Further, subjects will be warned not to become pregnant during the study and will be required to employ barrier contraceptive methods. Finally, participants who have an active condition that places them at an increased risk for osteoporosis will be excluded from this protocol.