RESUMO
OBJECTIVES: The primary aim of this study was to assess the transition from using the levonorgestrel-releasing intrauterine system (LNG IUS, 20 µg LNG/24 h) for reproductive-age contraception to using it as menopausal-age endometrial protection during estrogen replacement therapy (ERT). The transfer process was evaluated by assessment of the vaginal bleeding pattern. Continuation rates were also recorded. STUDY DESIGN: Open, multicentre, non-comparative study was conducted in 11 menopausal centres in Finland (3), The Netherlands (4), Belgium (2) and UK (2). Three hundred and ninety-four healthy women aged 46-51 years at entry with regular menstrual cycles, but without any climacteric symptoms, and who were willing to start oral or transdermal estrogen treatment for climacteric symptoms. If by 48 months a woman was not menopausal, she was not eligible for the ERT phase. Bleeding patterns were recorded in 90-day reference periods. RESULTS: One hundred and sixty-eight women were eligible for the ERT phase. The mean ± SD number of bleeding/spotting days was highest (49 ± 19 days) in the first 90-day reference period in the contraceptive phase. For subjects who switched to ERT this number was 10 ± 13 days in the last contraceptive reference period and decreased to 9 ± 12 days in the first and 6 ± 10 days in the last 90-day reference period of the ERT phase. For both spotting and bleeding days there was no statistically significant difference between the last contraceptive and the first reference period of the ERT phase. CONCLUSIONS: In general, the results indicate that continuing with the LNG IUS from contraception to ERT has no adverse effects on the vaginal bleeding profile, and show a positive effect of the combined estrogen and LNG IUS treatment on the quality of life.