en باکتری شناسی Bactriology پژوهشي Research <div style="text-align: justify;"><strong>Background and Aims: </strong>The aim was to determine the role of dominant serovars of <em>Listeria monocytogenes</em> (<em>L.&nbsp;monocytogenes</em>) in spontaneous abortions, using isolation methods and polymerase change reaction (PCR).<br> <strong>Materials and Methods:</strong> A total of 258 samples comprising of placental tissue, vaginal swabs and blood were collected from 123 patients with spontaneous abortion. <em>L.&nbsp;monocytogenes</em> was identified and confirmed by culture, biochemical reactions, serological tests, API system, CAMP (Christie, Atkins, Munch and Petersen) test, and hemolysis on sheep blood agar. Phosphatidyl inositol specific phospholipase C (PI-PLC) assay, followed by multiplex PCR was applied for detection of serotypes 1/2a and 4b.<br> <strong>Result</strong>: Out of 258 samples, 28 isolates of <em>L. monocytogenes </em>were identified &nbsp;&nbsp;by different methods. All of the isolates were confirmed by PCR. Of 28 isolated strains, 14(50%) belonged to serovar 1/2a, 10(35.7%) to serovar 4b and 4(14.3%) to other serovars.<br> <strong>Conclusions: </strong>Based on our study, serovars 1/2a and 4b are dominant serovars as causative agents of human spontaneous abortion due to <em>L.&nbsp;monocytogenes</em> in pregnant women.</div> Keywords: Humans, Listeria monocytogenes, spontaneous abortion, dominant serovars, hly gene, iap gene L. monocytogenes, Serovars, Spontaneous abortion 294 302 http://ijml.ssu.ac.ir/browse.php?a_code=A-10-280-1&slc_lang=en&sid=1 Maryam Rezaei M. Rezaei Rezai.m99@yahoo.com No Department of Microbiology, Kerman Branch, Islamic Azad University, Kerman, Iran. Nadia Kazemi Pour N. Kazemipour Rezai.m99@yahoo.com Yes Department of Microbiology, Kerman Branch, Islamic Azad University, Kerman, Iran. Jalil Vandyousefi J. Vandyousefi Rezai.m99@yahoo.com 0000-0002-6832-4322 No Shila Medical Diagnostic Laboratory, Tehran, Iran. Farokh Rokhbakhsh Zamin F. Rokhbakhsh zamin Rezai.m99@yahoo.com 0000-0002-6472-9461 No Department of Microbiology, Kerman Branch, Islamic Azad University, Kerman, Iran Gholamreza Irajian G. Irajian Rezai.m99@yahoo.com No Department of Microbiology, Iran University of Medical Sciences, Tehran, Iran.