Transvaginal measurement of cervical length in the prediction of successful induction of labour.

A total of 100 women with gestational ages of 34-42 weeks requiring induction of labour were consecutively recruited in a prospective study at the Medical College and Hospital, Baroda, India. The aim of this study was to determine the value of transvaginal measurement of cervical length in the prediction of successful vaginal delivery within 24 h. Induction of labour was carried out with Tab Misoprostol (25 microg). A Bishop's score and sonographic cervical assessment were performed prior to induction. Univariate and logistic regression analyses was used. A pre-induction cervical length measurement on TVS was an independent predictor of successful vaginal delivery. At < or =3 cm cervical length, the probability of a LSCS was <30%, while with 4 cm cervical length, the probability became >75%. One unit increase in cervical length increased the probability of LSCS by 45%. The cervical length measurement by TVS is therefore an independent predictor of successful labour induction and performs better than Bishop's score as a method of pre-induction cervical assessment.