Cervical Assessment by Transvaginal Ultrasound for Predicting Preterm Birth in Asymptomatic Women

Preterm birth (PTB) is defined as delivery before completing 37 weeks of gestation. It is the main cause of neonatal morbidity and mortality in the most countries. The inherent cervical length and strength are two main features of the cervix that determine whether or not a pregnant woman is at risk for PTB. Routine transvaginal cervical length screening was recommended for women with singleton pregnancy and history of prior spontaneous PTB, while the issue of universal cervical length screening and the screening in multiple gestations remain an object of debate. Strain sonoelastography and shear-wave sonoelastography have been used to evaluate the cervical stiffness in pregnant women, but the predictive value for PTB still requires further investigations. In this review, we will discuss the measurement methods of cervical length and cervical stiffness, and compare the value of cervical assessment by transvaginal ultrasound for predicting PTB in asymptomatic women.