[A prospective cohort study on effects of levonorgestrel-releasing intrauterine system for adenomyosis with severe dysmenorrhea].

OBJECTIVE: To investigate treatment effects of levonorgestrel-releasing intrauterine system (LNG-IUS) for adenomyosis with severe dysmenorrhea in a prospective cohort study.

METHODS: From December 2006 to December 2014, patients of symptomatic adenomyosis diagnosed by transvaginal ultrasound in outpatient or inpatient clinics of Peking Union Medical College Hospital were given the treatment of LNG-IUS. Before and after placement of LNG-IUS, all the patients' parameters were recorded prospectively, including symptoms and scores of dysmenorrhea, menstruation scores, biochemical indicators, physical parameters, carrying status of LNG-IUS, menstruation patterns and adverse effects. Changes of scores and patterns of pain during follow-up were analyzed.

RESULTS: Totally 1 100 women meets inclusion criteria, among which 640 cases (58.18%, 640/1 100) had severe dysmeorrhea, with median follow-up period of 35 months (range 1-60 months), and accumulative carrying rate of 65% at 60 months follow-up. After placement of LNG-IUS, scores of pain and ratio of severe dysmenorrhea had decreased significantly compared with baselines (all P<0.01), the scroes of visual analog scale (VAS) were 8.1±0.9, 5.5±2.4, 4.6±2.4, 3.3±2.2, 2.2±2.1, 2.2±1.8, 1.4±1.6 and 1.3±1.3 at 0, 3, 6, 12, 24, 36, 48 and 60 months respectively. During 36 months after placement of LNG-IUS, scores of pain had improved significantly compared with preceding period (all P<0.01). We found no universal dependent factors predicting improvement of pain, which was neither relevant with simultaneous changes of menstruation patterns nor adverse effects (all P>0.05).

CONCLUSION: LNG-IUS is effective for adenomyosis of severe dysmenorrhea. Improvement of pain is independent on patients characters, menstruation patterns or adverse effects.