The LNG-IUS study on adenomyosis: a 3-year follow-up study on the efficacy and side effects of the use of levonorgestrel intrauterine system for the treatment of dysmenorrhea associated with adenomyosis.

BACKGROUND: The objective of this study was to evaluate the efficacy and side effects of the levonorgestrel-releasing intrauterine system (LNG-IUS) in the treatment of moderate or severe dysmenorrhea associated with adenomyosis for a 3-year follow-up period.

STUDY DESIGN: The LNG-IUS was inserted into 94 women who had moderate or severe dysmenorrhea associated with adenomyosis diagnosed by transvaginal sonography during Cycle Days 5-7. A visual analogue scale (VAS) of dysmenorrhea, uterine volume and serum CA125 levels were used to assess the efficacy of the treatment at baseline and 3, 6, 12, 24 and 36 months after the LNG-IUS insertion. Side effects were recorded at every follow-up visit.

RESULTS: The VAS of dysmenorrhea dropped continuously and significantly from the baseline score of 77.9+/-14.7 to 11.8+/-17.9 after 36 months of the LNG-IUS insertion (p<.001). The uterine volume decreased significantly from 113.8+/-46.9 mL to 94.5+/-40.1 mL (p=.003) at 6 months and to 87.7+/-35.8 mL (p<.001) at 12 months and then rose slightly, but the variables at 24 and 36 months still decreased significantly in comparison with the baseline variable (p<.001). The serum CA125 levels reduced significantly starting from 6 months after device insertion (p<.001). The most common side effects were weight gain (28.7%), simple ovarian cyst formation (22.3%) and lower abdominal pain (12.8%). At 36 months, the overall satisfaction rate of the treatment was 72.5%.

CONCLUSIONS: The LNG-IUS appears to be an effective method in alleviating dysmenorrhea associated with adenomyosis during 3 years. It may be a valuable long-term alternative for the treatment of adenomyosis.