OBJECTIVE:To evaluate the central effect exerted by different progestins used for hormone replacement therapy.METHODS:Randomised, placebo-controlled study. One hundred-twenty postmenopausal women on continuous hormonal replacement therapy with transdermal estradiol (50 microg per day) associated, for 10 days every 28 days, with four different progestins: dydrogesterone (DYD; 10 mg per day; n = 20), medroxyprogesterone acetete (MPA; 10 mg per day; n = 20), nomegestrol acetate (NMG; 5 mg per day; n = 20) or norethisterone acetate (NETA; 10 mg per day; n = 20). Other 40 women, 10 for each treatment group, were used as controls and were monitored for a single cycle of 28 days during the administration of transdermal estradiol plus placebo. Morn...