A study on the efficacy and safety of long-term adjusted low-dose gonadotropin-releasing hormone agonist therapy for uterine fibroids and adenomyosis.

Abstract

Aim: To investigate the efficacy and safety of long-term adjusted low-dose gonadotropin-releasing hormone agonist therapy (GnRH agonist drawback therapy) with nafarelin acetate in patients with uterine fibroids and/or adenomyosis with menstrual symptoms.

Methods: This single-center, retrospective, observational study initially included 118 patients with uterine fibroids and/or adenomyosis with menstrual symptoms who had received GnRH agonist (nafarelin acetate) drawback therapy for at least 7 months between 2010 and 2020. Blood hemoglobin level, maximum fibroid diameter, area of the corpus uteri, blood estradiol level, daily dosage of nafarelin acetate, and bone density in the lumbar spine and femoral neck were assessed before and after the treatment initiation.

Results: The median treatment period was 28 months. Menstruation had ceased in all patients. The median hemoglobin level significantly increased from 8.6 to 13.2 g/dL before treatment and at 12 months after the treatment initiation in patients with fibroids and from 8.8 to 13.3 g/dL in patients with adenomyosis, respectively. Although the treatment did not exert a significant shrinking effect on the fibroids and adenomyosis, an increase in their size was not observed in any patient. The initial dose of nafarelin acetate was 400 μg/day and was lowered to 130 μg/day at 12 months. Only 29 patients (25%) had an estradiol level <30 pg/mL. The average rate of bone density change over 6 months was -1.23% in the lumbar spine and -1.12% in the femoral neck in patients with fibroids and -1.06% in the lumbar spine and -0.14% in the femoral neck in patients with adenomyosis, which were lower than the previously reported rates.

Conclusions: GnRH agonist drawback therapy was found to be useful for the long-term conservative treatment of uterine fibroids and adenomyosis. The treatment was safely and inexpensively performed with few adverse events.