 In the second phase, after a 2 month washout interval, the same subjects will again receive Lupron to suppress endogenous steroid production. After 4 weeks, at the beginning of ovarian activity resumption, the investigators will administer Letrozole 5mg for 14 days and again examine granulosa cell responses to FSH during recovery. Letrozole is a 3rd generation aromatase inhibitor which results in suppression of E2 production and increase in circulating serum androgen levels to about 40 greater than pre-treatment values. It is now also being used for ovulation induction. It has minimal side effects and is in general very well tolerated. By using Letrozole for 2 weeks after GnRH suppression of the ovaries, the investigators will more effectively increase the amount of circulating androgen while keeping estrogen at low levels, thereby allowing the investigators to more completely study the effects of isolated and elevated androgen levels on granulosa cell responses to FSH. By comparing results obtained in phase 1, the investigators will be able to determine if there is an androgen mediated response by granulosa cells to FSH stimulation in the absence of other ovarian steroids. Also, the addition of a control group will allow investigators to determine if the granulosa cell response is different between PCOS and normals. 