Trichomonas vaginalis infection is highly prevalent in the United States and worldwide. Traditional clinical diagnostic methods fail to identify more than half of these infections that, if left untreated, can result in adverse pregnancy outcomes and an exacerbated risk of both acquisition and transmission of HIV. Women bear a disproportionate amount of the burden of these infections, and testing among populations at risk for this disease should be provided. Molecular technologies have expanded our capacity for laboratory-based detection of infection and can be used on samples already being collected for chlamydia/gonorrhea screening. Trichomonas vaginalis is the causative agent of the most common nonviral sexually transmitted infection (STI) worldwide. However, our understanding of the epidemiology of trichomonas infection contains substantial gaps since this infection is often not screened for in large, population-based studies and the disease is not well monitored by public health agencies. The prevalence of Trichomonas infection is best documented in the United States, where the rates are consistently higher than those of Chlamydia trachomatis and Neisseria gonorrhoeae infect...