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 associated with the 52 mg levonorgestrel intrauterine system (LNG-IUS) and the 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 followed up to 6 months. Bleeding pattern was obtained through daily patient bleeding diaries. <b>Results:</b> From 2013 to 2014, we enrolled 512 women (LNG-IUS = 312 [median age: 32.0 years] and Cu-IUD = 200 [median age: 30.0 years]) from nine 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; .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; .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> = .0047). Both treatments had a high satisfaction rate among women at both the follow-up visits, and the 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; .0001), respectively. <b>Conclusion:</b> LNG-IUS post-abortion shows better bleeding patterns, and reduced dysmenorrhea and bleeding amount, but with a similar safety profile compared with Cu-IUD. <b>ClinicalTrials.gov identifier:</b> NCT01958684