 - Post-menopausal women aged 45-58 with an adequate hot flash frequency severity score. Post-menopause is defined as amenorrhea for at least 12 months, or post-hysterectomy for more than one year with follicle-stimulating hormone levels greater than or equal to 40 mIUmL and estradiol E2 levels of less than or equal to 20 pgmL, or greater than two months post oophorectomy. 