Background & objectives: Trichomonas vaginalis is a protozoan parasite lives and also causes symptoms in urogenital system of human. Trichomoniasis is the widest spread infection which is transmitted through sexual contact and more than 170 million people are a ffected with Trichomonas vaginalis in the world. Trichomonas vaginalis in women causes pelvic inflammatory disease, increase in the risk of fallopian tube dependent infertility, ectopic pregnancy, preterm labor, the birth of low weight infants and the increase in the possibility of HIV transmission. Considering the importance of Trichomonas vaginalis infection in pregnant women and lack of data from Ardabil city, this study was performed to identify this infection in pregnant women referred to health and medical centers of Ardabil city.

  Methods: Vaginal discharge from 500 pregnant women was collected with sterile swap and disposable speculum and examined for Trichomonas vaginalis by direct microscopic examination and cultured in Diamond specific medium. A testimonial and questionnaire were completed for each case and the results analyzed using chi-square test by SPSS statistical software version 19.

  Results: In this study, the culture of samples displayed 12 positive cases (2.4%). Furthermore, Trichomonas vaginalis trophozoites were observed in five cases (1%) with direct microscopic examination. Among 12 positive cases, five respondents (41.7%) were in age range of 16-25 years and seven (58.3%) in 26-35 years old. Among different clinical manifestations there was a significant relation between discharge and the infection.

  Conclusion: The present survey confirmed the presence of Trichomonas vaginalis infection in pregnant women of Ardabil city. Therefore, an effective healthcare program by health authorities for prevention of infection in this group seems to be needed.