The levonorgestrel intrauterine system in menopausal hormone replacement therapy: five-year experience

Objective: To study the long-term effects (5 years) of intrauterine levonorgestrel administration as the progestin part of continuous combined postmenopausal hormone replacement therapy. Design: Prospective clinical study. Setting: Department of obstetrics and gynecology at a central hospital. Patient(s): Twenty postmenopausal women with an intact uterus who had no contraindications to hormone replacement therapy and who wanted to take amenorrhea-inducing hormone replacement therapy to relieve their climacteric symptoms. Intervention(s): A percutaneous E-2 gel containing 1.5 mg of E-2 was administered daily and a levonorgestrel-releasing intrauterine device was used. Endometrial thickness was measured by vaginal ultrasonography. Endometrial sampling was performed yearly. Main Outcome Measure(s): Clinical compliance, profiles of bleeding, and endometrial thickness and morphology were monitored during 5 years of follow-up. Result(s): Eighteen women completed 1 year of follow-up. Fifteen of these women were willing to continue the study, and 12 of them completed 5 years of follow-up. Spotting was frequent during the first 6 months of the study and declined thereafter. At 1 year, 80% of the women were totally amenorrheic. Of the 15 women who continued the study, 12 were totally amenorrheic and 3 had problems with bleeding. The mean endometrial thickness was less than or equal to 3 mm during the study. Endometrial morphology showed epithelial atrophy accompanied by decidualization of the stroma in all 12 of the women who were followed up for 5 years. Conclusion(s): Intrauterine administration of progestin through a levonorgestrel-releasing intrauterine device is a good alternative as the progestin part of continuous combined hormone replacement therapy because it effectively opposes the estrogenic effects on the endometrium and induces amenorrhea in most cases. (Fertil Steril(R) 1999;72.161-3. (C) 1999 by American Society for Reproductive Medicine.)