A systematic review of the correlation between Trichomonas vaginalis infection and infertility

Trichomonas vaginalis (T. vaginalis) is an extracellular flagellated protozoan parasitizing the human genital and urinary tracts. T. vaginalis infection impacts human reproductive function, but whether it causes infertility is still a matter of debate.In this work, we consulted 205 relevant articles, which were classified into three categories: epidemiological investigations (100), review articles (43), and research articles (62). RevMan 5.4 was used to conduct a meta-analysis of the articles reporting epidemiological investigations comparing the incidence of T. vaginalis infection between infertile and fertile groups. Review and research articles were used to summarize the pathogenesis of infertility caused by T. vaginalis.The results indicated that rate of T. vaginalis infection in the infertile group was significantly higher than that in the fertile group. Moreover, the epidemiological surveys showed that the infertility rates of population infected with T. vaginalis were significantly higher than that of population without T. vaginalis infection. Nine out of ten (90%) related review articles stated that T. vaginalis infection causes infertility, and the review and research articles indicated the main pathogenic mechanisms of infertility caused by T. vaginalis were as follows: T. vaginalis impairs sperm quality, resulting in infertility; the immune response triggered by T. vaginalis infection impacts human reproductive function.Our results confirm that there is a correlation between T. vaginalis infection and infertility, and T. vaginalis infection can lead to infertility. The study provides a foundation for further investigations into its pathogenesis.