Expulsion and continuation rates of the levonorgestrel 52 mg intrauterine system was similar among nulligravid and parous users

To compare the expulsion and continuation rates of the levonorgestrel (LNG) 52 mg intrauterine system (IUS) in a cohort of nulligravid and parous users.We conducted a retrospective cohort study that included 996 participants in whom we placed an LNG-IUS, and the participants were monitored for up to 5 years after device placement. We identify 498 nulligravid participants in the medical record database between 2012 and 2020. Each nulligravida was paired with a parous users who had an LNG-IUS inserted on the same day, just before or after the nulligravida. The Kaplan-Meier method and the log-rank test were used to compare the survival curves of the two groups.By the fifth year of use, the expulsion rates were 7.6/100 and 8.2/100 women-years (W-Ys) and the continuation rates were 641/100 W-Ys and 65.4/100 W-Ys without difference among nulligravid and parous users, respectively (P = 0.782 and P = 0.564, respectively). We observed 29 and 31 expulsions among nulligravid and parous users, respectively.Nulligravid and parous participants who used the 52 mg LNG-IUS showed similar expulsion and continuation rates during five years of use.