Bleeding patterns with the 19.5 mg LNG-IUS, with special focus on the first year of use: implications for counselling

Abstract

Objective: The aim of the study was to provide an additional, detailed description of early bleeding patterns with the 19.5 mg levonorgestrel-releasing intrauterine system (LNG-IUS). Methods: We conducted a pooled analysis of the bleeding diaries of participants in a previously reported phase II randomised controlled study (n = 741) and a phase III study (n = 2904), with 2-year extension phase (n = 707), of the 19.5 mg LNG-IUS. Main outcome measures were the median number of bleeding and/or spotting days per 30-day reference period for 12 months and the influence of the previous contraceptive method and levonorgestrel dose on bleeding patterns. Results: The pooled analysis comprised 1697 women. There was a progressive decline in the number of bleeding and/or spotting days from month 1: the proportion of women with ≤4 bleeding and/or spotting days per month increased from 6.2% in month 1 to 15.8% in month 2, 26.0% in month 3, 39.3% in month 6 and 54.1% in month 12. The median number of bleeding and/or spotting days in month 1 was lowest in women who had previously been using an LNG-IUS. Conclusion: Analysis of bleeding diaries using 30-day reference periods provides detailed insight into bleeding changes in the first months following placement of the 19.5 mg LNG-IUS. This insight may prove useful when counselling women about contraceptive choice and method continuation.