(162) Switching and continuation patterns of consecutive IUD users - results from a large observational, real-world study in Europe (EURAS-LCS12)

Background: To date, limited published data is available on usage patterns among consecutive intrauterine device (IUD) users (i.e., users choosing re-insertion of an IUD directly after IUD removal).

Objectives: To describe patterns of consecutive IUD use in routine clinical practice in Europe.

Methods: Within the observational EURAS-LCS12 study across ten European countries, we identified consecutive IUD users, who received a new IUD immediately after removal of the previous device. IUDs were inserted between 2014 and 2023. Using descriptive statistics, we characterized switching and continuation patterns while differentiating IUD types and age groups. Observed IUD types comprised LNG devices of doses 13.5, 19.5, 52 mg, and Copper IUDs (Cu-IUD).

Results: Of 15,026 consecutive IUD users, most (12,105; 80.6%) continued to use the same IUD type when receiving a new IUD. Most LNG 52 mg IUD users (8,011/9,056; 88.4%) and Cu-IUD users (3,382/3,804; 88.9%) had been using their respective IUD type at replacement. Fewer LNG IUD 13.5 mg users (596/871; 68.44%) and LNG 19.5 mg users (116/1,286; 9.0%) had been using the same IUD type at replacement, possibly due to their relatively newer market entries (2014 and 2017, respectively). Among those who had changed the IUD type, a high proportion switched from Cu-IUD to any LNG-IUD (1,389/2,921; 47.6%). Interestingly, 53% of women switching from Cu-IUD to LNG 52 mg had an IUD indication of menorrhagia. Only a minor proportion switched from any LNG-IUD to Cu-IUD (422/2,921; 14.4%).
Users younger than 35 years changed the IUD type more often compared to women aged 35 and older (1,702/5,879; 29.0% vs. 1,219/9,147; 13.3%). Among younger women who changed their IUD type, most changes were observed from LNG 13.5 mg to LNG 19.5 mg (442; 26.0%), from Cu-IUD to LNG 52 mg (392; 23.0%), as well as from Cu-IUD to LNG 19.5 mg (219; 12.9%) and LNG 52 mg to LNG 19.5 mg (151; 8.9%).
Among older women who changed their IUD type (1,219), most changes were observed from Cu-IUD to LNG 52 mg (540; 44.3%), from LNG 52 mg to LNG 19.5 mg (167; 13.7%), from LNG 52 mg to Cu-IUD (166; 13.6%), from Cu-IUD to LNG 19.5 mg (100; 8.2%), and from LNG 13.5 mg to LNG 19.5 mg (91; 7.5%).

Conclusions: While most consecutive IUD users continued to use their respective IUD type, switching of IUD types occurred more often among younger women. Older women appeared to choose higher dose LNG-IUDs, possibly due to higher proportions of parous women who may seek long-term contraception or additional indications besides contraception. The additional indication of LNG 52 mg seems to play an important role for IUD switchers. Country-specific factors are likely to also affect choice of IUD type, therefore our results should be interpreted within the context of local clinical and reimbursement practices.