 The purpose of this trial is to determine the equivalence of 3 new formulations of a Premarinmedroxyprogesterone acetate MPA combination tablet to the currently marketed dosage form Prempro TM. This study will be performed in healthy postmenopausal women. Each subject will participate in the study for approximately 14 weeks, including a screening evaluation within 3 weeks before the study, and four, 6-day, 5-night inpatient periods with at least a 21-day washout interval between each dose administration. 