Vaginal Sonography of the Cervix for the Prediction of “Time to Delivery” in ART Twins Gestations

Abstract

AbstractThe present study aimed to determine a reliable tool to estimate the interval time to delivery in assisted conception twin pregnancies. Mid-gestation cervical length was prospectively measured using transvaginal sonography (TVS) during routine antenatal care. Fifty-seven of 101 suitable women were longitudinally followed and two TVS measurements of their cervical length were obtained, first at approximately 24 weeks gestation and then at approximately 27 weeks gestation. The mean cervical length decreased from 37 ± 12mm at first measurement to 34 ± 11mm at the second one. A linear regression model was found between the time interval of the first (R = 0.656, p < 0.001) and the second (R = 0.435, p < 0.001) assessments and the week of delivery. The current data confirm that the length of the preserved segment of the cervix is an important indicator of its competence. A simple equation using the cervical length (mm) divided by 3 can predict mid gestation scan-to-delivery interval in twin gestation.