 - Is post-menopausal defined as 12 months of spontaneous amenorrhea. A follicle stimulating hormone FSH level will be performed to confirm a post-menopausal status. For this study, FSH levels 40 mlUml is confirmatory. Females on hormone replacement therapy HRT and whose menopausal status is in doubt, HRT should be discontinued for 2 weeks and then the subject rescreened, as HRT can suppress FSH. 