Risks of Vaginal and Sexually Transmitted Infections With Copper Intrauterine Devices Compared to Levonorgestrel Intrauterine Devices [ID 1225]

INTRODUCTION: Copper (Cu-IUDs) and levonorgestrel intrauterine devices (LNG-IUDs) have differing effects on the vaginal mucosa. Copper IUDs have been reported to induce a local inflammatory response and to increase bacterial vaginosis risk. Levonorgestrel-IUD use suppresses endometrial growth and thickens cervical mucus. This study explores vaginal health outcomes and infection risks associated with Cu-IUDs compared to LNG-IUDs via retrospective chart review. METHODS: TriNetX platform was accessed to analyze risk outcomes of deidentified data. Using Healthcare Common Procedure Coding System and RxNorm codes, study cohorts (n=73,123) were created to include women with a Cu-IUD versus women with a LNG-IUD. Cohorts were matched for age, race, and ethnicity. Statistical analysis within 3 years of IUD placement used risk ratios (RRs), with 95% CI determining significance. RESULTS: Copper IUDs showed increased risk of chronic vulvitis (RR 1.46; CI, 1.37–1.56), acute vulvitis (RR 1.41; CI, 1.32–1.51), chlamydia (RR 1.41; CI, 1.29–1.53), chronic vaginitis (RR 1.40; CI, 1.32–1.50), syphilis (RR 1.40; CI, 1.23–1.60), gonorrhea (RR 1.37; CI, 1.25–1.51), human immunodeficiency virus (HIV) (RR 1.27; CI, 1.13–1.42), and acute vaginitis (RR 1.12; CI, 1.08–1.17). Copper IUDs showed a decreased risk for pelvic inflammatory disease (RR 0.85; CI, 0.77–0.98). P values for all risk differences are less than .005. There were no significant differences in risk for herpes simplex virus 2, anogenital warts, candidiasis, or trichomoniasis. CONCLUSIONS/IMPLICATIONS: Women using Cu-IUDs had increased risks for vulvitis, chlamydia, vaginitis, syphilis, gonorrhea, and HIV and decreased risk of pelvic inflammatory disease compared to LNG-IUDs. Further investigation of copper and levonorgestrel effects on the female reproductive microbiome compared to women who do not use IUDs is warranted.