Translabial Tridimensional Ultrasound Imaging of Uterine Cervical Dilatation in First Stage of Labor

Sudy objective- To assess the use of non invasive intrapartum translabial 3D-US in the diagnosis of latent to active phase transition defined as an increase in cervical dilatation from 3cm to 5cm, and to compare it to digital vaginal examination. Study methods- An observational prospective double blind clinical study. Hourly consecutive translabial 3D-US volumes are obtained in singleton term patients admitted to delivery room. Sonographers are blind to patient’s digital vaginal examination partogram. Patients and delivery room personnel are blind to sonographic results. Obtained volumes will be processed offline. Ultrasound maximal cervical diameter and vaginal digital examination will be compared.