Sustained-release estradiol implants and a levonorgestrel-releasing intrauterine device in hormone replacement therapy

Suhonen, S. P.; Allonen, H. O.; Lahteenmaki, P.

OBJECTIVE: Efficacy and acceptability of continuous combined parenteral hormone replacement consisting of subdermal estradiol delivery and intrauterine progestin delivery was studied. STUDY DESIGN: Thirty-six volunteer postmenopausal women seeking treatment for climacteric symptoms participated in this open, randomized study. The subjects received either one or three subdermal implants with a controlled daily release of estradiol in vitro. Progestin therapy was carried out with a levonorgestrel-releasing intrauterine device. Climacteric symptoms and serum concentrations of estrone, estradiol, follicle-stimulating hormone, and sex hormone-binding globulin were followed up for 1 year. The subjects kept daily records of bleeding. RESULTS: Serum estradiol concentrations with the set of three implants were stable during the follow-up period; the range of mean serum estradiol concentrations was 45 to 57 pg/ml. Four women, all from the group with one implant, discontinued the study after 6 months because of the return of climacteric symptoms. In spite of different daily estradiol doses, the patterns of bleeding were similar in both groups. At the end of the follow-up year 72% of the women had had no bleeding or spotting in the previous 3 months. CONCLUSION: Our results suggest that by combining subdermal and intrauterine steroid delivery systems postmenopausal hormone replacement therapy can be carried out successfully without daily effort and with minimal or no bleeding.