A Retrospective Analysis of the Correlation between Trichomonas Vaginalis Infection and Infertility

Background: 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.Methods: In this work, we consulted 237 relevant articles, which were classified into three categories: epidemiological investigations (104), review articles (40), 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.Results: The results indicated that rate of T. vaginalis infection in the infertile group was lower than that in the fertile group. However, an epidemiological survey showed that the infertility rate of population infected with T. vaginalis was significantly higher than that of population without T. vaginalis infection. Most review articles stated that T. vaginalis infection causes infertility, while a small fraction of these articles were inconclusive. The conclusion that T. vaginalis infection can lead to infertility is supported by the research articles, which indicated the main pathogenic mechanisms are as follows: T. vaginalis impairs sperm quality, resulting in infertility; the immune response triggered by T. vaginalis infection impacts human reproductive function; and T. vaginalis impairs ovum quality, resulting in infertility.Conclusion: Our study confirmed that T. vaginalis infection can lead to infertility and provides a foundation for further investigations into its pathogenesis.