In this open observational study we evaluated the effectiveness of a levonorgestrel-releasing intrauterine device (LNG-IUD) in the treatment of myoma-related menorrhagia. Nineteen patients with recurrent menorrhagia lasting more than 3 months and with fibromyomatosus uterus were treated for 12 months with a LNG-IUD releasing 20 micro g/day of levonorgestrel. Menstrual blood loss, measured objectively by the pictorial blood loss assessment chart score (PBAC), level of serum hemoglobin and pattern of uterine bleeding were recorded at 3, 6, 9 and 12-month follow-up visits. Median monthly PBAC score during the two menstrual cycles before treatment was 310. After LNG-IUD, the PBAC score gradually decreased from a median value of 186 at 3 months to a median value of 155, 108 and 96 at 6, 9 and 12 months of treatment, respectively. Despite the statistically significant reduction of PBAC score, persistent menorrhagia, defined as a monthly PBAC score of 100 or higher, was observed at 12 months in 14 patients, whereas only one woman was amenorrheic and 4 were hypomenorrheic. In conclusion our study demonstrates the clinical reduced effectiveness of LNG-IUD in the treatment of myoma-related menorrhagia.