The Levonorgestrel 52 mg Intrauterine System Is Effective and Safe for Six Years [13M

Abstract

INTRODUCTION: Liletta®, a levonorgestrel (LNG) 52mg contraceptive intrauterine system (IUS), is under investigation in an ongoing multicenter trial for up to ten years of use. Here we evaluate six-year efficacy and safety data. METHODS: We enrolled women aged 16-45 years with participants aged 36-45 years undergoing safety evaluation only in this IRB-approved trial. After IUS placement, we followed 1,568 women aged 16-35 years and 146 women aged 36-45 years, assessing pregnancy rates through six years and safety outcomes in all women regardless of duration of use. RESULTS: The 16–35 year-old subjects included 986 (57.5%) nulliparous and 433 (25.3%) obese women. To date, more than 375 women have completed 6 years of use; more than 125 have completed 8 years. Nine pregnancies occurred over 6 years including two in year 1, four in year 2, one each in years 3-5, and none in year 6. Six (67%) pregnancies were ectopic. The cumulative life-table pregnancy rate through year 6 was .87 (95% CI .44-1.70). Two perforations following IUS placement were diagnosed within the first year and none since. Expulsion occurred in 68 (4.0%) participants, most (50 [73.5%]) during the first year with 2 per year in years 6 and 7. Pelvic infection was diagnosed in 15 (.9%) women, most (11 [73.3%]) occurring after 6 or more months of use. Only 40 (2.3%) women discontinued due to bleeding complaints, primarily (n=30 [75.0%]) in the first 2 years. CONCLUSION: The LNG 52 mg IUS is highly effective over six years of use and has an excellent extended safety profile.