RESUMEN
BACKGROUND: In this open prospective study the correlation between bleeding patterns and endometrial histology has been evaluated in 101 postmenopausal women after 2 years of continuous sequential hormone replacement therapy (HRT). METHODS: All patients received continuous transdermal 17-b-estradiol supplementation, 0.05 mg/daily, with cyclic progestogen for 12 days every month. The progestogen was: dydrogesterone 10 mg/daily (56 cases); nomegestrol 5 mg/daily (15 cases); MAP 10 mg/daily (15 cases); norethisterone 0.25 mg/daily (15 cases). The changes in the characteristics of bleeding pattern and endometrial biopsy were performed in 90 of 101 patients, at the 10-12th of progestogen therapy. RESULTS: The endometrial pattern was secretory in 60 cases, proliferative in 5 and atrophic in 22. In 3 cases the endometrial histology showed a simple hyperplasia. The bleeding generally starts 2 days after the end of progestogen therapy (13th +/- 2.9 day), with a mean duration of 4 days (4 +/- 2.8); in 21 patients (~20%) the bleeding is reduced. The endometrial histological characteristics haven't any influence on the bleeding pattern. CONCLUSIONS: In this study there was a low incidence of simple hyperplasia (3%), but the characteristics of bleeding don't permit to suspect this hyperplasia.