Uterine bleeding pattern during low dosage Noretisterone acetate and 17-b-Estradiol treatment in postmenopausal patients

BACKGROUND: Recent years have been characterized by progressive optimization of postmenopausal hormonal replacement therapy. More physiological therapeutic protocols have been, in fact, proposed to control the possible symptomatology and to prevent the associated risks, with estro-progestinic compounds characterized by lower effective dosages and suitable for the single patient need. However this therapy is not widely accepted by the women from our country for the fears and the inconvenience raised around such side effects as abnormal uterine bleeding and spotting. Aim: to obtain a good compliance and clinical benefits a continuous administration protocol of the hormonal replacement therapy, alternatively to the sequential one has been proposed. METHODS: Our research group has been observing a sample of 42 patients for 12 months, taking oral 17-b-estradiol 1 mg/noretisterone 0.5 mg in continuous administration. All of them were aged from 42 to 63 years and had been in symptomatic menopause for at least 3 months. The characteristics, the onset and the trend of vaginal bleeding were registered in appropriate monthly diaries. Endometrial thickness was evaluated by transvaginal sonography before starting the administration, not exceeding 4 mm in all the women considered. RESULTS: The incidence of bleeding (calculated as a percent of women who experienced a vaginal bleeding for al least a day during a menstrual cycle) was from 26% to 32% in the 1st trimester, reducing during the following months. At 6 months of therapy only 5% of women reported evident vaginal bleeding; at 12 months 90% of women complained with absence of bleeding or spotting. At 12 months no women showed an endometrial thickness over 6 mm. CONCLUSIONS: This observational study suggests that the majority of treated patients proved to be positively responsive to the treatment and that the 17-b-estradiol 1 mg/noretisterone 0.5 mg association reduces the incidence of bleeding and spotting with a sufficient endometrial protection from hyperplasia.