Risk Factors for Prevalent and Incident Trichomonas vaginalis Among Women Attending Three Sexually Transmitted Disease Clinics

Goal: Trichomonas vaginalis is the most common nonviral sexually transmitted infection in the United States and may be associated with adverse birth outcomes and may also increase susceptibility to or transmissibility of human immunodeficiency virus. The purpose of this analysis is to describe the epidemiology of T. vaginalis in Sexually Transmitted Disease clinics and characterize the risk factors associated with prevalent and incident T. vaginalis within the same population. Methods: We analyzed data from visits occurring during February 1999-December 2001 from 3 sexually transmitted disease clinics in Newark, NJ; Long Beach, CA; and Denver, CO. Data were analyzed from 1462 women aged 15 to 39 years who were tested by culture at their initial visit for T. vaginalis, and for 1269 women with at least 1 follow-up visit. Risk factors for prevalent infections at baseline and incident infections among treated or previously uninfected women were assessed. Results: At baseline, 13.0% of the women had a prevalent infection; risk factors included the following: older age (≥20 years), black race, having less than 12 years of education, and having a concurrent chlamydial infection. At follow-up, 4.6% of women had an incident infection; risk factors included the following: older age (35-39 years), black race, having a concurrent chlamydial infection, having had multiple sexual partners in the 3 months before incident infection, and having had T. vaginalis at the visit before their incident infection. Conclusions: T. vaginalis incidence is high in women. Risk factors for prevalent and incident infection are similar. T. vaginalis was associated with older age in women, unlike other sexually transmitted infections.