Effect of Combined Estradiol and Drospirenone (E + DRSP) Versus Combined Estradiol and Medroxyprogesterone Acetate (E + MPA) Endothelial Function

This study compares the effects of two common hormone medications on the heart and blood
vessels of healthy post-menopausal women over the age of 45.

The study will take place over the course of about 5 months. Each subject will take two
different medications over two six-week periods. They will be randomized at the beginning of
the study to either estradiol+medroxyprogesterone acetate or estradiol+drospirenone for the
first period, and will receive the other medication the second six-weeks of the study. At
the very beginning of the study and at the end of each six-week treatment period, subjects
will come to the hospital various tests including non-invasive blood vessel imaging tests,
blood draws to test the levels of certain hormones in the body, an oral glucose tolerance
test, a test to monitor renal blood flow, and 24-hour blood pressure monitoring. Between
treatment periods, there will be a four-week medication-free washout period.