Purpose of lnvestigation: To evaluate the prevalence and effects of inherited thrombophilia caused by factor V Leiden, prothrombinG 20210A and methylenetetrahydrofolate reductase (MTHFR) C677T mutations in women with recurrent pregnancy loss. Methods: A study group of 97 women with recurent miscarriages and a control group of 71 healthy pregnant women were included in the study. Genotype analyses for factor V Leiden, prothrombin G20210A and MTHFR C677T polymorphisms were performed by real-time polymerase chain reaction (RT-PCR). Results: The frequency of factor V Leiden, prothrombin G20210A and MTHFR C677T mutations were similar in both the study and control group. There were eight patients (8.2%) who had more than one gene mutation in the studygroup and one patient in the control group (1.4%). This difference was not statistically significant. Study group patients (n = 97) were compared in terms of the number of miscarriages and the abortion week, in adition to being a carrier of factor V Leiden and MTHFR C677T gene mutations. No statistically significant correlation was found between being a factor V Leiden and MTHFR C677T mutation carrier with either the number of miscarriages or the abortion week. Conclusion: Factor V Leiden, prothrombin G20210A and MTHFR C677T gene mutations are not individually related with recurrent pregnancy loss. However, combined gene mutation status may be associated with recurrent miscarriages.