Treatment of symptomatic adenomyosis with the levonorgestrel-releasing intrauterine system.

Objective: To determine the long-term effects of using the levonorgestrel-releasing intrauterine system (LNG-IUS) to treat symptomatic adenomyosis.

Method: A prospective longitudinal study was conducted among 1100 women who received the LNG-IUS at a tertiary teaching hospital in China between December 10, 2006, and December 24, 2014. All participants had symptomatic adenomyosis (visual analogue scale [VAS] ≥7 and/or pictorial blood loss assessment chart [PBAC] score >100) diagnosed by transvaginal sonography. Follow-up was at 3, 6, 12, 24, 36, 48, and 60 months after LNG-IUS placement. The primary outcome was symptom relief. Secondary outcomes included LNG-IUS retention status; changes in uterine volume; serum levels of cancer antigen 125 (CA125); menstruation pattern; and adverse events.

Results: In all, 374 (33.7%) participants completed 60 months of LNG-IUS treatment. The VAS, verbal rating scale, PBAC score, hemoglobin level, uterine volume, and serum CA125 level all showed marked improvements at this time point when compared with baseline (P<0.05 for all comparisons). The cumulative retention rate of LNG-IUS was 56.2%. Changes in menstruation pattern at 60 months included amenorrhea (n=97, 25.9%) and shortened periods (n=82, 21.9%). The incidence of adverse events was <10% and not considered notable.

Conclusions: Long-term use of LNG-IUS was effective and acceptable for the treatment of symptomatic adenomyosis. Registered at clinicaltrials.gov (NCT03027648).