Background and Objective: Preterm labor is one of the most significant challenges to maternal and neonatal health. In rare instances, cervical insufficiency may culminate in preterm delivery. The clinical distinction between high-risk and low-risk patients for preterm labor remains challenging. The objective of the present study is to predict preterm delivery and the timing of labor through the evaluation of cervical length changes.
Methods: This cross-sectional study was conducted on 80 pregnant women hospitalized due to preterm labor. Upon admission, all patients underwent transvaginal ultrasonography. Based on the cervical length measured at admission, they were divided into two groups: high-risk (cervical length<15 mm) and low-risk (cervical length>15 mm). The following variables were assessed and compared between the groups: maternal age, gestational age, cervical length, delivery time, body mass index (BMI), and progesterone use.
Findings: The mean level of change in cervical length between admission and 48 hours after arrest of labor was 2.09±6.47 mm (p=0.021). The mean maternal age was 26.9±6.6 years, and the mean gestational age at admission was 31.16±1.35 weeks. The mean cervical length at admission was 29.24±3.66 mm, whereas 48 hours after arrest of labor, it measured 31.33±2.14 mm. Preterm labor within 7 days of admission occurred in 7.5% of patients, and 83.8% delivered before 34 weeks of gestation. A cervical length change (∆_CL) of less than -5.5 mm demonstrated a sensitivity of 66.7%, while a ∆_CL of less than -6.5 mm demonstrated a sensitivity of 85% for predicting preterm labor.
Conclusion: The present study demonstrated that significant changes in cervical length can serve as an important predictive marker for preterm labor in high-risk pregnant women. Specific thresholds of cervical length changes, particularly significant reductions, exhibit a strong correlation with the likelihood of preterm labor.