Expulsion and continuation rates of the 52 mg levonorgestrel intrauterine system in adolescents and adult women

Objective To compare the continuation rates, expulsion, and other reasons for discontinuation of the hormonal intrauterine device with 52 mg of levonorgestrel (52 mg LNG-IUD) in adolescents and adult women.Methods We conducted a retrospective cohort study that included 393 women in whom we placed a 52 mg LNG-IUD and followed up to 5 years. We created two retrospective cohorts, one with 131 adolescents (aged between 12 and 19 years) and the other with 262 women aged ≥20 years. Each adolescent was paired with two adult women who had the same parity and who had a 52 mg LNG-IUD inserted on the same day. We used the Mann-Whitney test to compare numerical variables in both groups, the Kaplan-Meier method, and the log-rank test to compare the continuation, expulsion and other reasons for IUD discontinuation of the two groups.Results Age of the adolescents and adult women were mean ± SD 18.1 (±1.1) and 31 (±6.8) years, respectively (p = 0.015). Continuation rates by the fifth year of use were 55.6/100 women-years (W-Y) and 70.3/100 W-Y among adolescents and adult women (p = 0.106); and expulsion rates were 8.4/100 and 6.0/100 W-Y, respectively (p = 0.463). Adolescents had a lower continuation rate during 3 to 5 years of follow-up (p = 0.011) and a high rate of removals due to bleeding/pain (18.5 ± 5.7/100 W-Y vs 6.4/100 ± 2.1 W-Y, p = 0.039).Conclusion Adolescents who used the 52 mg LNG-IUD showed a lower continuation rate 3–5 years after device placement than adult women. The expulsion rates were similar in both groups.