Blood samples will be collected for estradiol at baseline,1,2,3,6 and 15 months; lipid profile at baseline, 9 and 21 months; coagulation tests at baseline,1 and 3 months; cervical cytology examinations at baseline, 12 and 24 months; mammography at baseline and at the last study visit in all the patients who would complete > 12 months of follow-up.