The Prevalence of Trichomonas vaginalis Infection among Reproductive-Age Women in the United States, 2001-2004

Abstract

Background. Trichomonas vaginalis infection is a common sexually transmitted protozoal infection and is associated with several adverse health outcomes, such as preterm birth, delivery of a low–birth weight infant, and facilitation of sexual transmission of human immunodeficiency virus. The annual incidence in the United States has been estimated to be 3–5 million cases. However, there are no data on the prevalence of trichomoniasis among all reproductive-age women. We estimated the prevalence of T. vaginalis infection from a nationally representative sample of women in the United States. Methods. Women aged 14–49 years who participated in the National Health and Examination Survey cycles for 2001–2004 provided self-collected vaginal swab specimens. The vaginal fluids extracted from these swabs were evaluated for the presence of T. vaginalis using polymerase chain reaction. Results. Overall, 3754 (81%) of 4646 women provided swab specimens. The prevalence of T. vaginalis infection was 3.1% (95% confidence interval [CI], 2.3%–4.3%); for non-Hispanic white women, it was 1.3% (95% CI, 0.7%–2.3%); for Mexican American women, it was 1.8% (95% CI, 0.9%–3.7%); and for non-Hispanic black women, it was 13.3% (95% CI, 10.0%–17.7%). Factors that remained associated with increased likelihood of T. vaginalis infection in multivariable analyses included non-Hispanic black race/ethnicity, being born in the United States, a greater number of lifetime sex partners, increasing age, lower educational level, poverty, and douching. Conclusions. The prevalence of T. vaginalis infection among women in the United States was 3.1%. A significant racial disparity exists; the prevalence among non-Hispanic black women was 10.3 times higher than that among non-Hispanic white and Mexican American women. Optimal prevention and control strategies for T. vaginalis infection should be explored as a means of closing the racial disparity gaps and decreasing adverse health outcomes due to T. vaginalis infection.