The predictive nature of uterocervical angles in the termination of second trimester pregnancy

The Uterocervical Angle Combined with Bishop Score as a Predictor for Successful Induction of Labor in Term Vaginal Delivery

The objective of this study was to determine the value of uterocervical angle (UCA) in predicting successful induction of labor (IOL) in singleton pregnant women compared to the Bishop score and cervical length (CL). A total of 205 normal term, singleton labor-induction cases were analyzed. Successful IOL was defined as the onset of active labor of induction. A comparative analysis was performed to evaluate the effectiveness of UCA, Bishop score, and CL in predicting IOL. Compared to the non-successful IOL group, the women in the successful IOL group had significantly wider UCA (p = 0.012) and higher Bishop score (p = 0.001); however, the CL was not significantly different (p = 0.130). UCA alone did not perform better than the Bishop score when predicting successful IOL. However, UCA combined with the Bishop score showed higher performance in predicting IOL (combined UCA > 108.4° and favorable Bishop score as sensitivity of 44.6%, specificity of 96.0%, PPV of 96.2%, and NPV of 43.6; combined UCA > 108.4° or favorable Bishop score as sensitivity of 85.7%, specificity of 50.0%, PPV of 78.7%, and NPV of 61.9). In conclusion, UCA combined with Bishop score may be an effective sonographic method for predicting successful IOL.

Uterocervical angle: an ultrasound screening tool to predict satisfactory response to labor induction

Background: A wide uterocervical angle >95° detected during the second trimester was associated with an increased risk for spontaneous preterm birth.Objective: We aimed to determine whether an ultrasonographic marker, uterocervical angle, correlates with satisfactory response to labor induction.Study design: We conducted a prospective cohort study from May 2016 through December 2017 of singleton term gestations undergoing transvaginal ultrasound for cervical length screening and uterocervical angle measurement. Uterocervical angle was measured between the lower uterine segment and the cervical canal. Latent phase duration >720 min was accepted to be a prolonged latent phase. The primary outcome was a prediction of satisfactory response to labor induction (latent phase duration <720 min).Results: Both anterior uterocervical angle (AUC = 0.802, p < .001) and the cervical length (AUC = 0.679, p < .05) significantly predicted satisfactory response to labor induction. Optimal cutoff value was obtained at the value of 97° (64% sensitivity, 91% specificity) for anterior uterocervical angle and 27 mm (64% sensitivity, 64% specificity) for the cervical length. Kaplan-Meier survival analysis showed that duration from labor induction to delivery was significantly higher in a group with longer cervical length (p = .04), additionally labor induction to delivery time was significantly higher in a group with lower UCA (p = .04).Conclusions: Both the cervical length and anterior uterocervical length were predictors for the satisfactory response to labor induction, and both parameters were found to be significantly associated with time from induction to delivery in survival analysis.

Can uterocervical angles successfully predict induction of labor in nulliparous women?

PURPOSE

Induction of labor is a common practice in obstetrics. In recent years, a newer ultrasonographic parameter called the uterocervical angle (UCA) has been identified as a predictive tool for births. Our purpose is to investigate the role of UCA in predicting successful induction of labor.

METHODS

The nulliparous term pregnancies (n:150) were grouped into successful/failed inductions of labor based on their progress into the active phase of labor after the administration of prostaglandin E2 (dinoprostone). The pre-induction cervical length (CL) and UCA were compared in the two groups. The study population was further grouped according to their modes of delivery and pre-induction UCAs were compared among the subgroups.

RESULTS

The mean UCAs were not significant among the successful induction and failed induction groups (105.46 ± 20.54 degrees in the successful group and 110.57 ± 13.46 degrees in the failed group). However, UCAs significantly varied among the modes of delivery subgroups. The median UCA was significantly higher in patients who delivered vaginally after a successful induction of labor than in patients who delivered via cesarean section. The median UCA value was lowest in patients who had a successful induction of labor but ended up having a cesarean section (Fig. 2). Further, the duration of the active phase of labor negatively correlated with the UCA but not the CL (rho=-0.23, p = 0.02). There was also a negative correlation between the CL and the UCA in patients who delivered vaginally after successful induction of labor (rho= -0.21, p = 0.03).

CONCLUSION

The UCA is a promising ultrasonographic marker in obstetrics. Although the pre-induction UCA did not predict the outcome of labor induction, patients with broader pre-induction UCAs were prone to have a shorter duration of active phase. The pre-induction CL and UCA are inversely corraleted in nulliparous women who delivered vaginally after a successful induction of labor.