Neurophysiology of Postpartum Depression in an Experimental Model of Pregnancy and Parturition

Inclusion Criteria: Group 1: Women with a history of PPD 1. A history of a major depression episode that occurred within two months of childbirth (as determined by a SCID interview) and remitted at least one year prior to enrollment in the study; 2. has been well for a minimum of one year; 3. a regular menstrual cycle for at least three months; 4. age 22-50; 5. not pregnant, not lactating and in good medical health; 6. medication free (not including birth control pills; participants may opt to temporarily discontinue birth control pills to participate); 7. no history of puerperal suicide attempts or psychotic episodes requiring hospitalization. Group 2: Healthy Controls 1\) Controls will meet all inclusion criteria specified above except they must not have any past or present Axis I diagnosis or evidence of menstrually related mood disorders. A structured clinical interview (SCID) will be administered to all women prior to study entry. Any woman with a current axis I psychiatric diagnosis will be excluded from participating in this protocol. Exclusion Criteria: Patients will not be permitted to enter this protocol if they have important clinical or laboratory abnormalities including any of the following: * current axis I psychiatric diagnosis * endometriosis; * undiagnosed enlargement of the ovaries; * liver disease; * breast cancer; * a history of blood clots in the legs or lungs; * undiagnosed vaginal bleeding; * porphyria; * diabetes mellitus; * malignant melanoma; * gallbladder or pancreatic disease; * heart or kidney disease; * cerebrovascular disease (stroke); * cigarette smoking; * a history of suicide attempts or psychotic episodes requiring hospitalization; * recurrent migraine headaches; * pregnancy (patients will be warned not to become pregnant during the study and will be required to agree to employ barrier contraceptive methods); * pregnancy-related medical conditions such as hyperemesis, pre-toxemia and toxemia, deep vein thrombosis (DVT) and bleeding diathesis; Any woman with a first degree relative (immediate family) with either ovarian cancer, premenopausal breast cancer or breast cancer presenting in both breasts or any woman who has multiple family members (greater than three relatives) with postmenopausal breast cancer will also be excluded from participating in this protocol; Any woman meeting the Stages of Reproductive Aging Workshop Criteria (STRAW) for perimenopause will be excluded from participation. Specifically, we will exclude any woman with an elevated plasma follicle stimulating hormone (FSH) level (\> 14 IU/L) and with menstrual cycle variability of \> 7 days different from their normal cycle length.