Meta-Analysis of Intrauterine Device Use and Risk of Endometrial Cancer

• Published in: Annals of epidemiology 2008-06, Vol.18 (6), p.492-499
• Main Authors: Beining, Robin M., MS, Dennis, Leslie K., MS, PhD, Smith, Elaine M., MPH, PhD, Dokras, Anuja, MD, PhD
• Format: Article
• Language: English
• Subjects: Adult; Aged; Endometrial Cancer; Endometrial Neoplasms - epidemiology; Female; Humans; Internal Medicine; Intrauterine Device; Intrauterine Devices - utilization; Meta-analysis; Middle Aged; Review; Risk Factors
• ISSN: 1047-2797; 1873-2585
• DOI: 10.1016/j.annepidem.2007.11.011

Purpose We sought to study the association between intrauterine device (IUD) use and endometrial cancer. Methods A comprehensive search of literature published through April 2007 was conducted, studies reviewed, and data abstracted. Data from ten studies were pooled and analyzed using both fixed- and random-effects models to examine the association of ever use of an IUD and endometrial cancer. Results Based on the random effects model, a protective crude association between IUD use and endometrial cancer was observed (odds ratio [OR] = 0.39; 95% confidence interval [CI] = 0.29–0.51; heterogeneity p < 0.001) with a pooled adjusted risk of OR = 0.54 (95% CI, 0.47–0.63; heterogeneity p = 0.40). A decreased risk of endometrial cancer also was seen for increased years of IUD use (OR for 5 years of use 0.88; 95% CI = 0.84–0.92; n = 5; heterogeneity p = 0.14), increased years since last IUD use (OR for 5 years of use 0.91; 95% CI, 0.86–0.95; n = 4; heterogeneity p = 0.02), and increased years since first IUD use (OR for 5 years of use 0.89; 95% CI, 0.83–0.95; n = 4; heterogeneity p = 0.04). Conclusions Our results suggest that nonhormonal IUD use may be associated with a decreased risk for endometrial cancer; however, the exact mechanism for this association is unclear. Future investigations should address the difference in the proposed association by specific type of IUDs.