en Microbiology and Anatomy Microbiology and Anatomy Original Research Original Research &nbsp;&nbsp;<strong>&nbsp; Background: </strong>Gardnerella vaginalis is considered as the predominant microorganism found in bacterial vaginosis (BV). The aim of this study was to evaluate the prevalence of virulence factors in G. vaginalis associated with BV or non-BV cases and their correlations with this disorder.<br> <strong>&nbsp;&nbsp;&nbsp; Methods: </strong>A total of 102 vaginal specimens were collected from patients during their visit to Akbar Abadi hospital in Tehran, Iran. Bacterial vaginosis was determined by Nugent score and Amsel&rsquo;s criteria. Polymerase chain reaction (PCR) was used for the detection of G. vaginalis 16S rRNA, vaginolysin, sialidase and phospholipase genes. To evaluate the association between the presence of vly, pho, and sld genes and BV. Pearson Chi-square test was applied using SPSS software. P-value &le;0.05 was considered as significant.<br> <strong>&nbsp;&nbsp; Results:</strong> Totally, 27.4% of the patients were suffering from BV. Gardnerella vaginalis was found in 100% women with BV and in 56.7% women with normal vaginal discharge. The prevalence of vly, sld and pho genes in BV-associated G. vaginalis was 10 (35.7%) (95% CI [0.18, 0.53]), 19 (67.8%) (95% CI [0.51, 0.85]) and 6 (21.4%) (95% CI [0.06, 0.37]), respectively. The prevalence of the aforementioned genes in non-BV associated G. vaginalis was 20 (47.6%) (95% CI [0.33, 0.63]), 28 (66.6%) (95% CI [0.52, 0.81]), and 5 (11.9%) (95% CI [0.02, 0.22]), respectively. Our results showed no statistically significant association between the presence of the virulence genes and BV associatedness of this microorganism<strong>. </strong><br> <strong>&nbsp;&nbsp; Conclusion: </strong>Our results showed the presence of <em>G. vaginalis </em>in all BV patients and relatively high prevalence in healthy individuals. The prevalence rates of the three virulence genes were different in BV and non-BV associated <em>G. vaginalis</em>; however, the differences were not statistically significant.&nbsp;&nbsp; Gardnerella vaginalis, Bacterial vaginosis, PCR 517 522 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1256-1&slc_lang=en&sid=1 Rokhsareh Mohammadzadeh rokhsare.mohamadzade@gmail.com 200319475328460062484 200319475328460062484 No Microbial Biotechnology Research Center & Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Behrooz Sadeghi Kalani behroz.sadeghi@gmail.com 200319475328460062485 200319475328460062485 No Microbial Biotechnology Research Center & Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Maryam Kashanian Maryamkashanian@yahoo.com 200319475328460062486 200319475328460062486 No Department of Obstetrics and Gynecology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Mojgan Oshaghi Mobin255@gmail.com 200319475328460062487 200319475328460062487 No Department of Laboratory Sciences, School of Allied Health, Iran University of Medical Sciences, Tehran, Iran Nour Amirmozafari amirmozafari@yahoo.com 200319475328460062488 200319475328460062488 Yes Microbial Biotechnology Research Center & Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran