Second-Trimester Cervical Shear Wave Elastography Combined With Cervical Length for the Prediction of Spontaneous Preterm Birth.

Abstract

The goal of this study was to explore the value of shear wave elastography (SWE) combined with cervical length (CL) in the prediction of spontaneous preterm birth (sPTB) between 18 and 24 weeks of gestation. In this study, SWE was used to evaluate four regions of the cervix: the external and anterior lip (region A1), the external and posterior lip (region A2), the internal and anterior lip (region A3) and the internal and posterior lip (region A4). The cervical Young's modulus (YM) was compared between women who spontaneously delivered prematurely (<37 wk) and those who delivered full term. Finally, the predictive power of SWE was evaluated using receiver operating characteristic analysis. Overall, 773 patients were included in this study, of whom 60 (7.8%) had a sPTB. In the univariate analysis, prior sPTB, history of spontaneous abortion, history of cervical surgery, CL and YM at the anterior portion of both the internal and external os and the posterior portion of the internal os were associated with sPTB (p < 0.05). Multiple regression analyses were performed to develop the prediction probability for sPTB. YM and CL were independent predictors of sPTB in asymptomatic women, and the combination of YM and CL improved the ability to predict sPTB (area under the receiver operating characteristic curve=0.98, 95% confidence interval: 0.97-0.99, p < 0.001). The interventions had relatively little impact on the outcome indicators measured. Cervical YM added to the CL may improve the predictive performance of second-trimester transvaginal ultrasound for sPTB.