 - This protocol is a screening protocol for an estradiol treatment study 03-M-0161 for which the exclusion criteria include the current use of antidepressant medications. However, antidepressants will not be withheld from subjects who need or want them. Immediately after screening subjects will either be enrolled in the estrogen treatment study or in traditional therapy until care can be transitioned to the community. There are few exclusion criteria for the evaluation component of this protocol; however, all women will undergo a structured diagnostic interview Those women who will be asked to participate in the companion protocol evaluating the efficacy of estradiol administration in PPD will meet either research diagnostic criteria for minor depression with at least three core symptoms SADS-L 90 or major depression SCID-IV 91 of not greater than moderate severity on the Global Assessment of Functioning Scale GAF 91 and will not meet DSM-IV criteria 9 suicide or require immediate treatment. Subjects meeting major depression with greater than moderate severity may participate in the evaluation phase of this study but will be offered a referral to an outside facility for standard antidepressant treatment i.e., they are not candidates for participation in the IRB approved treatment protocol. 