CYCLICAL ADMINISTRATION OF NOMEGESTROL AC ETATE DOES NOT ALTER THE VASODILATION EXERTED BY ESTRADIOL ON UTERINE ARTERY

Uterine artery blood flow was analyzed in 8 menopausal women receiving hormonal replacement therapy consisting of transdermal E(2) (0,05 mg/ 24 h) administered without interruption for 12 weeks in combination wi th a cyclical supply of Nomegestrol acetate (5 mg/24 h) for the last 1 3 days of each four week treatment cycle. Uterine artery flow was anal yzed using transvaginal pulsed Doppler making semi quantitative measur ements of Doppler flow waves by calculation of the pulsatility index ( PI). Before treatment (baseline) uterine artery PI was elevated at 3.7 +/- 0.7 (mean +/- SD) and decreased significantly under the influence of E(2) to reach 1.9 +/- 0.8 after 2 weeks of treatment. This effect of E(2) was not altered by the cyclical addition of Nomegestrol acetat e. On the 3rd month of treatment, uterine artery PI values were lower than seen during the first month and no difference was observed betwee n measurements made while receiving E(2) (week 10) or E(2) and Nomeges trol acetate (week 12). These data indicate that cyclical administrati on of the progestin Nomegestrol acetate does not interfere with the va scular effects of E(2) lowering the uterine artery PI a reflector of t he impedance to flow.