Vaginal microbial flora as a cofactor in the pathogenesis of uterine cervical intraepithelial neoplasia.

The vaginal microbial flora of 106 women with histopathologically confirmed cervical intraepithelial neoplasia and 79 women without disease, was evaluated for Gardnerella vaginalis, Trichomonas vaginalis, Candida albicans and other yeasts. Flora morphology was assessed by gram staining of secretions. Cervical cultures were examined for Herpes Simplex virus, Cytomegalovirus and Neisseria gonorrhoeae. Chlamydia trachomatis antigens in cervical secretions were detected by enzyme immunoassay. Human Papillomavirus was identified by koilocytosis in cytologic or histopathologic specimens. Human Papillomavirus infection (P less than 0.00001), vaginal infection with Mycoplasma hominis (P = 0.012) and abnormal vaginal flora (P = 0.006) were significantly associated with CIN, suggesting that CIN may be promoted by vaginal microorganisms in conjunction with human papillomavirus cervical infection.