Comparative analysis of transvaginal sonographic cervical assessment and Bishop Score in predicting labour induction success at a tertiary hospital in Ghana.

Objectives: To compare transvaginal sonographic cervical assessment and Bishop Score (BS) in predicting successful induction (vaginal delivery within 24 hours) among low-risk postdate pregnancies (late term and post-term) induced at a tertiary hospital in Ghana.

Design: An analytical cross-sectional study conducted between 2022 and 2023.

Participants: Women with low-risk post-date pregnancies admitted for induction of labour. Transvaginal sonographic cervical assessment and BS were done for participants before the start of induction.

Main outcome measures: The predictive abilities of the transvaginal sonographic cervical length (TVSCL), the BS and the posterior cervical angle (PCA) in predicting vaginal delivery.

Results: Of 184 women recruited, 168 were included in the final analysis. The rate of vaginal delivery was 82.1%. Successful induction occurred in 117/168 participants (69.9%) [CI:62.1-76.5]. TVSCL ≤ 2.5cm was comparable in accuracy with BS ≥ 4 in predicting vaginal delivery. For predicting vaginal delivery within 24 hours, the accuracy of the PCA at ≥ 106 was marginally higher than the BS [AUC: 62.3; 61.0], although both were statistically significant. 95% of women preferred transvaginal sonographic assessment.

Conclusion: BS and transvaginal sonographic assessment were comparable in predicting delivery when used for pre-induction cervical assessment. Transvaginal sonographic cervical assessment was better tolerated.

Funding: None declared.