Bleeding pattern difference between levonorgestrel-intrauterine system and copper-intrauterine devices inserted immediately post-abortion: a multicenter, prospective, observational cohort study in Chinese women

<b>Background:</b> To describe the bleeding pattern (primary outcome), side effects, treatment satisfaction, and 6-month continuity rates of 52 mg levonorgestrel-intrauterine system (LNG-IUS) and copper intrauterine device (Cu-IUD) inserted immediately after abortion. <b>Methods:</b> This multicenter, prospective, observational cohort study enrolled healthy women (aged ≥18 years) inserted with LNG-IUS or Cu-IUD immediately after first-trimester surgical abortion and were followed up to 6 months. Bleeding pattern was obtained through daily patient bleeding diaries. <b>Results:</b> From 2013–2014, we enrolled 512 women [LNG-IUS = 312 (median age: 32.0 years) and Cu-IUD = 200 (median age: 30.0 years)] from 9 Chinese centers. LNG-IUS resulted in a significantly lower number of bleeding/spotting days in the second 90-day reference period compared with Cu-IUD (median 14.5 vs. 18.0 days, <i>P</i>&lt;0.0001). Amenorrhea rate (no bleeding/spotting day in the second 90-day reference period) and no menstrual bleeding rate (absence of bleeding days in the second 90-day reference period) were significantly higher in LNG-IUS compared to Cu-IUD (13.9% vs. 0% and 39.5% vs. 0%; <i>P</i>&lt;0.001 for all). No dysmenorrhea was higher at the last follow-up in LNG-IUS users than Cu-IUD users (81.2% vs. 76%; <i>P</i> = 0.0047). Both treatments had a high satisfaction rate among women at both the follow-up visits, and majority of them continued with the treatment. The rates of adverse events (e.g. oligomenorrhea, amenorrhea) in the LNG-IUS and Cu-IUD groups were 77.2% and 44.5% (<i>P</i>&lt;0.0001), respectively. <b>Conclusion:</b> LNG-IUS post-abortion shows better bleeding patterns, and reduced dysmenorrhea and bleeding amount, but with similar safety profile compared with Cu-IUD. ClinicalTrials.gov identifier: NCT01958684