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Demographic, Reproductive, and Medical Risk Factors for Intrauterine Device Expulsion
Mary S Anthony1, Xiaolei Zhou, Juliane Schoendorf
1RTI Health Solutions, Research Triangle Park, North Carolina; Bayer OY, Espoo, Finland ; the Department of Obstetrics and Gynecology, University of Washington, and Kaiser Permanente Washington Health Research Institute, Seattle, Washington; the Department of Research & Evaluation, Kaiser Permanente Southern California, the Department of Health Systems Science and the Department of Clinical Science, Kaiser Permanente Bernard J. Tyson School of Medicine, Pasadena, the Division of Research, Kaiser Permanente Northern California, Oakland, and the Department of Obstetrics & Gynecology, Kaiser Permanente West Los Angeles Medical Center, Los Angeles, California; the Regenstrief Institute, and Indiana University, Indianapolis, Indiana; RTI Health Solutions, Waltham, Massachusetts; Bayer Pharmaceuticals, Whippany, New Jersey; and Bayer AG, Berlin, Germany .
Insights
Heavy menstrual bleeding and younger age are key risk factors for intrauterine device (IUD) expulsion. Certain demographic groups, including Asian or Pacific Islander individuals, face higher expulsion risks, warranting further investigation.
Area of Science:
- Reproductive Health
- Contraception
- Medical Device Efficacy
Background:
- Intrauterine devices (IUDs) are highly effective long-term contraceptives.
- Understanding IUD expulsion risk factors is crucial for patient counseling and optimizing contraceptive choices.
Purpose of the Study:
- To investigate the association between demographic and clinical factors and the risk of IUD expulsion.
- To identify specific risk factors that predict IUD expulsion in a large cohort.
Main Methods:
- A U.S. cohort study (APEX-IUD) analyzed electronic health records from 2001-2018.
- Cox regression models were used to estimate hazard ratios for IUD expulsion, adjusting for various risk factors.
Main Results:
- Heavy menstrual bleeding was the strongest predictor of IUD expulsion.
- Higher risk was observed in individuals with overweight/obesity, younger age (≤24 years), and high parity (≥4).
- Non-Hispanic White individuals had the lowest risk, while Asian or Pacific Islander individuals had the highest adjusted risk.
Conclusions:
- Physiologic factors like age, BMI, heavy menstrual bleeding, and parity influence IUD expulsion.
- The elevated expulsion risk among individuals of color requires further research.
- While IUD expulsion is uncommon, patient counseling on associated risks is essential.
Objective:
To explore to what extent intrauterine device (IUD) expulsion is associated with demographic and clinical risk factors.
Methods:
The APEX-IUD (Association of Perforation and Expulsion of IntraUterine Devices) study was a U.S. cohort study using electronic health records from three integrated health care systems (Kaiser Permanente Northern California, Southern California, and Washington) and a health care information exchange (Regenstrief Institute). These analyses included individuals aged 50 years or younger with IUD insertions from 2001 to 2018. Intrauterine device expulsion cumulative incidence and incidence rates were estimated. Using Cox regression models, hazard ratios with 95% CIs were estimated before and after adjustment for risk factors of interest (age, race and ethnicity, parity, body mass index [BMI], heavy menstrual bleeding, and dysmenorrhea) and potential confounders.
Results:
In total, 228,834 individuals with IUD insertion and no delivery in the previous 52 weeks were identified (184,733 [80.7%] with levonorgestrel-releasing intrauterine system). Diagnosis of heavy menstrual bleeding-particularly a diagnosis in both recent and past periods-was the strongest risk factor for IUD expulsion. Categories with the highest risk of IUD expulsion within each risk factor included individuals diagnosed with overweight, obesity, and morbid obesity; those in younger age groups, especially among those aged 24 years or younger; and in those with parity of four or more. Non-Hispanic White individuals had the lowest incidence and risk, and after adjustment, Asian or Pacific Islander individuals had the highest risk. Dysmenorrhea was not independently associated with expulsion risk when adjusting for heavy menstrual bleeding.
Conclusion:
Most risk factors for expulsion identified in this study appear consistent with known physiologic factors that affect uterine anatomy and physiology (age, BMI, heavy menstrual bleeding, parity). The increased risk of IUD expulsion among individuals of color warrants further investigation. Intrauterine devices are an effective long-term contraceptive; expulsion is uncommon, but patients should be counseled accordingly.
Funding Source:
Bayer AG.
Clinical Trial Registration:
EU PAS register, EUPAS33461.
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