Background. If the pregnancy attempt fails, it may become a stressful event. Therefore, in many cases, problem solving can lead to greater satisfaction and cohesion of couples and prevent psychological and social harm to families. The aim of this study was to determine the significant difference in the expression of miR-146a miRNA in maternal blood between the control and observation groups and to determine whether the miRNA can be used as diagnostic biomarkers or not. Methods. The present study is a basic and descriptive survey in terms of data analysis. The samples included pregnant women referred to Tabriz University of Jahad from September 2019 to February 2021. We used Exel, Spss v.21 and Roc software for data analysis. Data were prepared in Exel software with reference gene and by calculating CT. Were used in Roc software. Results. The results showed a difference between the control and observation groups. Early detection of recurrent miscarriage should be used in these mothers. Conclusion. Through using diagnostic kits of the studied miRNAs, effective steps can be taken for early detection, prevention of abortion, and reducing the heavy psychological, economic, and social burden on families. Therefore, it is suggested that diagnostic kits be made for these biomarkers and used in infertility centers. Practical Implications. Among the practical implications of this study, we can mention the diagnosis and prevention of abortion, which can reduce the burden on families and society.