Predictive value of cervical length by ultrasound and cervical strain elastography in labor induction at term

Abstract

Objective This study aimed to examine whether addition of cervical elastographic parameters measured by ElastoScan for the cervix (E-cervix) improves the predictive value of cervical length (CL) in induction of labor at term by dinoprostone. Methods We conducted a prospective, observational study between January 2020 and June 2020 in term primiparous women (n = 73) who were scheduled for labor induction by a 10-mg dinoprostone vaginal insert. The time intervals from the start of labor induction to regular uterine contractions and to vaginal delivery were calculated as the primary outcomes. We divided subjects into two groups using a threshold of 24 hours. Ultrasound measurements were compared between the two groups and the area under the curve (AUC) of the prediction model was calculated. Results Women who delivered vaginally within 24 hours had a shorter CL and softer cervix than those who delivered after 24 hours. The combination of CL and elastographic parameters increased the AUC to 0.672 compared with CL alone (AUC = 0.637). Conclusions Measurement by E-cervix is relatively reproducible. Addition of cervical strain elastography slightly improves the predictive performance of CL in vaginal delivery within 24 hours. This technique is a promising ancillary tool for use with ultrasound.

Prediction model for successful induction of labor by cervical strain elastography diagnosed at late-term pregnancy in nulliparous women: a prospective cohort study

“…The functional cervical length can be measured using the E-Cervix system and a four-point ROI that traces the endocervical lining of a straight or curved cervix [ 27 ]. The accuracy and repeatability of cervical length measurements have been improved using semi-automatic systems, and cervical length has become a valuable parameter for predicting the success of IOL [ 13 , 28 – 31 ]. Hamza et al reported that a cervical length of 25 mm, the presence of cervical funneling, and a shorter cervical length were significantly associated with successful IOL within 24 h [ 28 ].…”

“…Eser et al reported that cervical length is significantly related to a satisfactory response to IOL and the time from induction to delivery [ 30 ]. Zhou et al found that a short cervical length and a soft cervix are significantly associated with vaginal delivery within 24 h, and that the use of cervical strain elastography could improve the predictive performance of cervical length for a successful vaginal delivery within 24 h of IOL [ 31 ].…”

Can Transvaginal Cervical Elastography predict the success of induction of labor with oxytocin?

“…Several studies have analyzed the connection between elastographic findings and induction of labor by prostaglandins [21]. Carlson et al revealed that cervical softening after misoprostol was clearly associated by the measurements in elastosonography, although, they did not provide a correlation with induction success [22].…”

Repeatability and reproducibility of quantitative cervical strain elastography (E-Cervix) in pregnancy

“…In one of the reports published in 2019, the inclusion of the ECI parameter in the logistic regression model containing three other parameters (CL, prepregnancy BMI and gestational age at examination) for patients in the second trimester of pregnancy with cervix length ≥ 1.5 cm significantly increased the overall diagnostic accuracy of the test compared to screening based solely on CL 4 . In the perinatal period, some of the E-Cervix parameters (HR, IOS) in combination with CL allowed for increasing the predictive capacity of the model evaluating the chance of vaginal delivery in the next 24 h during labour induction with the use of a dinporoston vaginal insert 6 . Perhaps further research in elastography will contribute to its wider use in obstetrics.…”

“…Cervical hardness is a standard element assessed in the bimanual examination of the pelvis during pregnancy, and it is also an element of the Bishop scale assessment 2 . Consistency examination can be used in the prediction of preterm labour 3 , 4 , in the prediction of a spontaneous onset of labour and in evaluations of the effectiveness of the induction of labour (IOL) 5 , 6 . The two main techniques of USE are strain elastography (SE) and shear wave elastography (SWE), differing in terms of the stress type applied to tissue.…”