UC Davis

INTRODUCTION:: Liletta is a levonorgestrel 52 mg contraceptive intrauterine system (IUS) currently approved for contraception for up to three years based on an ongoing multicenter trial evaluating the product for up to seven years of use. We evaluated four-year efficacy and safety data for Liletta. METHODS:: Women aged 16-45 years were enrolled and followed in the clinical trial. Women aged 36-45 years received the IUS for safety evaluation only. We assessed four-year pregnancy rates (by Pearl Index and life-table analysis) and safety outcomes. RESULTS:: Successful IUS placement occurred in 1,568 (98%) women aged 16-35 years and 146 (97%) women aged 36-45 years, including 1,011 (57.7%) nulliparous and 438 (25.1%) obese women. Among women 16-35 years at enrollment, eight pregnancies occurred including one following perforation and one following expulsion. Six (75%) pregnancies were ectopic. The eight pregnancies included three nulliparous women and one obese woman. The Pearl Index in the first year was .15 (95% CI .02-.55). Cumulative life-table pregnancy rates through years two, three and four were .49 (95% CI .22-1.09), .60 (95% CI .28-1.26) and .78 (95% CI .37, 1.60). Perforation following IUS placement occurred in two (0.1%) women; both were diagnosed within the first year. Expulsion was reported in 63 (3.7%) participants, most (50 [80.6%]) during the first year of use. Pelvic infection was diagnosed in 12 (.7%) women. Only 38 (2.2%) women discontinued due to bleeding complaints. CONCLUSION:: Liletta is highly effective and safe over four years of use in nulliparous and parous women as well as non-obese and obese women.