Calcification mechanisms and atherosclerosis is opening new frontiers in research. An experimental protocol was done to evaluate the repercussions of hormone therapy with progesterone in oophorectomized rabbits submitted to the atherogenic diet on the development of atherosclerotic lesions induced in animals. From these findings, we can conclude that the therapy with medroxy-progesterone acetate at doses of 5 and 10mg per day in oophorectomized New Zealand rabbits submitted to the atherogenic diet, revealed at the end of 90days: serum dosages -absence of changes in cholesterol and triglyceride levels; aorta -absence of differences in the area and height of the lesions, in the intima and middle layers; fewer aortas with calcium deposits; coronary arteries with smaller number of compromised arteries.