Study of pre induction transvaginal ultra-sonographic cervical length and its comparison with bishop score in predicting successful labor induction

Santosh Khajotia, Madhuri Sharma, Mool Chand Khichar, Manoj Gupta, Kavita Choudhary


Background: Induction of labor means initiation of uterine contraction, after period of viability by any method (medical, surgical or combined) before spontaneous onset of labor for the purpose of vaginal delivery. The condition of cervix or favorability is important for successful labor induction. Assessment of cervix has been used as a predictor of successful vaginal delivery. Induction of labor carried out in approximately 20% of all pregnancies. Aim and objectives of the current study were to compare the predictive value of trans-vaginal ultra-sonographic measurement of cervical length versus Bishop score prior to induction of labor in predicting the mode of delivery and maternal and fetal outcome.

Methods: This prospective observational study was conducted in the department of obstetrics and gynecology, Sardar Patel medical college and associated group of hospitals, Bikaner between February to November 2020. Study group included 100 pregnant women in which induction of labor was performed at 37-42 weeks of gestation.

Results: Bishop Score appears to be a better predictor than the cervical length with sensitivity of 1.00 and a specificity of 0.12 compared to 0.52 and 1.00 respectively. In the receiver operating characteristic curves, the cut-off point for the prediction of successful induction taken was 2.6 cm cervical length and >4 for the bishop score.

Conclusions: TVS cervical length could be used as alternative to Bishop score for prediction of successful labor induction in the sitting where the appropriate equipment and expertise are available. Bishop score and TVS cervical length both are good predictors of successful induction of labor.



Cervical length, TVS, USG, Bishop score

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