Design of the Association of Uterine Perforation and Expulsion of Intrauterine Device study: a multisite retrospective cohort study

BackgroundIntrauterine devices are effective and safe, long-acting reversible contraceptives, but the risk of uterine perforation occurs with an estimated incidence 1 to 2 per 1000 insertions. The European Active Surveillance Study for Intrauterine Devices, a prospective observational study that enrolled 61,448 participants (2006–2012), found women breastfeeding at time device insertion or inserted ?36 weeks after delivery had higher perforation. Association Uterine Perforation Expulsion Device (APEX-IUD) was Food Drug Administration–mandated designed reflect current United States clinical practice. aims APEX-IUD were evaluate intrauterine device–related expulsion among who within 12 months insertion.ObjectiveWe aimed describe design, methodology, analytical plan present population characteristics, size factor groups, duration follow-up.Study DesignAPEX-IUD retrospective cohort conducted in 4 organizations access electronic health records: Kaiser Permanente Northern California, Southern Washington, Regenstrief Institute Indiana. Variables identified through structured data (eg, diagnostic, procedural, medication codes) unstructured notes) via natural language processing. Outcomes include expulsion; potential factors insertion, postpartum timing type, menorrhagia diagnosis year before insertion. Covariates demographic procedure-related variables, such as difficult first date inclusion eligible varies by research site (from January 1, 2001 2010). Follow-up begins ends occurrence outcome interest, censoring event (device removal reinsertion, pregnancy, hysterectomy, sterilization, expiration, death, disenrollment, last encounter), end period (June 30, 2018). Comparisons levels exposure variables made using Cox regression models confounding adjusted propensity score weighting overlap weights.ResultsThe includes 326,658 least during (Kaiser 161,442; 123,214; 20,526; Institute, 21,476). median continuous enrollment 90 (site medians 74–177) months. mean age 32 years, racially ethnically diverse across sites. body mass index 28.5 kg/m2, included study, 10.0% ?12 5.3% fibroids, 10% recent smokers; furthermore, these women, 79.4% levonorgestrel-releasing devices, 19.5% copper devices. Across sites, 97,824 ?52 delivery, which 94,817 (97%) status determined; addition, 228,834 >52 no evidence their record.ConclusionCombining from multiple sites allowed large population. Collaboration clinicians design validation outcomes ensured results Results this will provide valuable information based on real-world about clinicians. We follow-up. weights. record. Combining