VALIDATION OF CERVICAL LENGTH AND BISHOP SCORE AS PREDICTORS OF SUCCESSFUL TERM LABOR INDUCTION- A PROSPECTIVE VALIDATION STUDY

Abstract

Objective: To evaluate how accurately cervical length (CL) and Bishop score(BS) can predict successful induction of labor at term.

Materials and Methods: A prospective validation study was carried out at Lady Reading Hospital, Peshawar on  489 women at 37–42 weeks of gestation, aged 15–45 years, and scheduled for labor induction were included through consecutive sampling. Women with previous cesarean section, myomectomy, twin pregnancies, or prior use of oxytocin or prostaglandins were excluded. All participants were informed about the study purpose, assured of confidentiality, and provided written consent. CL was measured using transvaginal ultrasound, and BS was assessed clinically. Labor was induced with 25 µg misoprostol placed in the posterior vaginal fornix, and participants were observed for 24 hours. Data were analyzed using R (version 4.3.1) and MedCalc to calculate diagnostic statistics, and generate ROC curves.

Results: The average age was 27.1±3.1 years. CL under 27 mm predicted successful induction with 77.4% sensitivity, 60.9% specificity, and 75.3% overall accuracy. BS above 5 showed 80.0% sensitivity, 59.4% specificity, and 77.3% accuracy. ROC analysis showed areas under the curve of 0.87 for CL and 0.86 for BS.

Conclusion: Both BS and CLare effective tools for predicting successful term induction.