Anterior uterocervical angle: is it an ultrasonographic screening tool that estimates the latent phase duration in post term pregnancies?

Objectives: In recent years, in addition to cervical length measurement, a new ultrasonographic parameter has been defined as uterocervical angle (UCA), which can be used in the prediction of preterm labor. In this study,we evaluated the place of uterocervical angle in predicting the latent phase duration in postterm pregnancies.

Material and methods: This prospective study consists of 90 pregnant women aged between 18 to 40 years who were hospitalized with a diagnose of late term pregnancy. Pregnant women with a latent phase duration of 1200 minutes or less were defined as Group 1. Patients with latent phase duration over 1200 minutes were defined as Group 2. All patients' age, BMI, smoke, cervical length measurements, uterocervical angle, latent and active phase of labor durations, length of the third stage and delivery types were compared.

Results: The UCA median value of group 1 was 120 (94-147), and group 2 was 99 (94-105) (p < 0.001). CL medians of Groups 1 and 2 were 29 (17-43) and 28 (27-41) respectively (p: 0.871). UCA (AUC: 0.917, p < 0.0001) significantly predicted prolonged latent phase duration. Optimal cut off value was obtained at the value of 105 degree (100% sensitivity, 75% specificity) for UCA. Kaplan-Meier survival analysis showed that duration of labor was significantly higher in a group with low UCA (p: 0.013).

Conclusions: UCA can be a successful tool that can be used to predict duration of labor in cases of postterm pregnancies with medical induction.