Preterm birth before 37 wk of gestation is called premature birth. Corticotropin-releasing hormone (CRH) and CRH-binding protein (BP) act on various maternal and fetal tissues during pregnancy, such as the myometrium, which regulates the transition from the dormant phase of the uterus to the active phase. Studies have shown that mir-200c and mir-181a interact with CRH and CRH-BP. The present study aimed to investigate the expression of mir-200c, mir-181a, CRH, and CRH-BP in women with a history of preterm birth. In this case-control study, the gene expression level of mir-200c, mir-181a, CRH, and CRH-BP in placental tissue samples obtained from 48 women with a history of preterm labor was assessed in the Mojibian hospital of Yazd, Iran, from January to March 2023. Differences between mir-200c, mir-181a CRH, and CRH-BP gene expressions among cases and controls were assessed. The outcomes indicated that the expression of CRH increased with going on to the regular parturition time (p 0.001). While outcomes indicated, CRH-BP decreased with going on to the regular parturition time (p 0.001). In addition, the results showed that the expression of mir-181a increased and mir-200c decreased with approaching the normal delivery time (p 0.001). In conclusion, the expressions of mir-200c, mir-181a, CRH, and CRH-BP were dissimilar in different weeks of gestation. It could be proposed to use mir-200c, mir-181a, CRH, and CRH-BP as biomarkers to weigh the exact delivery time, which could minimize the side effects of preterm labor for the mother and fetus.