OBJECTIVES: In 2001, excessive uterine bleeding was the cause of 1.4 million physician visits in the US. Beyond offering contraceptive benefits, Levonorgestrel-Releasing Intrauterine System (LNG-IUS) is an effective alternative to traditional management of menstrual bleeding disorders. The objective was to describe a population on LNG-IUS and assess contraceptive and non-contraceptive outcomes. METHODS: Women °Ý18 years of age with LNG-IUS and °Ý1 year of continuous enrollment pre- and post-insertion were identified via a retrospective cohort design utilizing claims data from a Michigan vertically integrated healthcare system (Jan. 2000 - Dec. 2005). Patterns of LNG-IUS use, number of obstetric- and gynecology-related visits, percent of patients with menorrhagia, dysmenorrhea, dysfunctional uterine bleeding, and abnormal uterine bleeding were compared pre- and post-insertion, along with gynecology-related costs. RESULTS: A total of 152 women (mean age 35 ± 8) met study inclusion criteria. Two nested cohorts were distinguished further based on follow-up length as 2-year pre/post (N=73) and 3-year pre/post (N=29) groups. Over 90% had a single insertion and °Ü4% a LNG-IUS -related complication (e.g. expulsion, perforation, or infection). No LNG-IUS patient experienced a pregnancy with no obstetric-related visits post-insertion for all groups. Thirteen percent of women experienced menorrhagia in the year preceding insertion, down to 12.5%, 1.2% and 0% in the 1, 2 and 3 years post-insertion. Subsequently, mean number of gynecology-related visits decreased from 4 to 2; 7 to 4 and 9 to 4 from the pre- to the post-insertion period for the 1, 2, and 3-year follow-up groups, respectively. Among non-hysterectomized women, mean gynecology-related costs decreased from $1,646 per patient in the 3 years preceding LNG-IUS to $1355 in the 3 years post-insertion. CONCLUSION: LNG-IUS avoided pregnancy in all patients and led to decreased bleeding-related events and gynecology-related costs starting in the second year post-insertion. Benefits should become more apparent with longer follow-up.