Objective: This study aims to investigate the effects of uterine leiomyomas’ on cervical length in pregnant women during mid-trimester ultrasound scan. Material and Methods: In thisstudy, 1908 pregnant women aged 18-44 years were evaluated via abdominal and transvaginal ultrasounds in the mid-trimester (18-24 weeks). The number, size, type and location of the leiomyomas were screened and recorded. Cervical length was measured transvaginally on an emptybladder. Short cervix was defined as lower than 25 mm. Pregnant women with leiomyoma werecompared with pregnant women without leiomyoma regarding cervical length and short cervix incidence. Results: Eighty (4.2%) patients were diagnosed with uterine leiomyoma and the mean diameter of uterine leiomyomas was 31.4 mm. The mean cervical length of the leiomyoma group wassignificantly lesser than that in pregnant women without leiomyomas (p=0.001). The number ofwomen with a short cervix was higher in the leiomyoma group than the controls (p=0.001). Therewas a significant positive correlation between age and leiomyoma prevalence (r=0.294, p=0.021).There was a significant negative correlation between myoma size and cervical length in womenwith only one leiomyoma (r=-0.325, p=0.015). Conclusion: Pregnant women with leiomyoma havehigher incidence of short cervix. Leiomyomas could negatively affect cervical length.