en 23926530 Background: Recurrent pregnancy loss is (RPL) a heterogeneous condition. While the role of acquired thrombophilia has been accepted as an etiology for RPL, the contribution of specific inherited thrombophilic gene polymorphisms to the disorder has been remained controversial. Methods: One hundred women with a history of two or more consecutive abortions and 100 women with at least two live births and no miscarriages were included in the study and evaluated for the presence of 11 thrombophilic gene polymorphisms (Factor V LEIDEN, Factor V 4070 A/G, Factor V 5279 A/G, Factor XIII 103 G/T, Factor XIII 614 A/T, Factor XIII 1694 C/T, PAI-1 -675 4G/5G, ITGB3 1565 T/C, β-Fibrinogen -455G/A, MTHFR 677 C/T, MTHFR 1298 A/C) using PCR-RFLP technique. The data were statistically analyzed using Mann-Whitney test and logistic regression model. Results: There was no relation between factor XIII 103G/T gene polymorphism with increased risk of RPL. However, the other 10 gene polymorphisms were found to be associated with increased/decreased risk of RPL. Multiple logistic regression model for analyzing the simultaneous effects of these polymorphisms on the risk of RPL showed that six of these 11 polymorphisms (Factor V 1691G/A, Factor V 5279A/G, Factor XIII 614A/T, β-Fibrinogen -455G/A, ITGB3 1565T/C, and MTHFR 1298A/ C) were associated with RPL. Conclusion: It is possible to calculate the risk of abortion in a patient with RPL by determining only six of the 10 polymorphisms that are individually associated with RPL. PCR-RFLP, Recurrent Pregnancy Loss, Thrombophilic gene 089 95 https://www.jri.ir/article/494 https://www.jri.ir/documents/fullpaper/en/494.pdf RahelehTorabiDepartment of Medical Genetics, National Institute for Genetic Engineering and Biotechnology (NIGEB), Tehran, Iranراحلهترابی743SaeedZareiMonoclonal Antibody Research Center, Avicenna Research Institute (ACECR), Tehran, Iranسعیدزارعی683HojjatZeraatiDepartment of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iranحجتزراعتی481Amir HassanZarnaniImmunology Research Center, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iranامیرحسنزرنانی241Mohammad MehdiAkhondiReproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iranمحمدمهدیآخوندی21RezaHadaviMonoclonal Antibody Research Center, Avicenna Research Institute (ACECR), Tehran, Iranرضاهادوی769ElhamSavadi-ShirazReproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran746MahmoodJeddi-TehraniMonoclonal Antibody Research Center, Avicenna Research Institute (ACECR), Tehran, Iranمحمود جدی‌تهرانیmahjed@yahoo.com54