Comparison between Fetal Fibronectin Versus Ultrasonographic Assessment of The Cervical Length in Patients with Unfavourable Cervix in Prediction of Successful Induction of Labor

Background: When the advantages of delivery for the mother or the foetus outweigh the hazards of continuing the pregnancy, labour should be induced.
Objective: The purpose of the study was to examine the effectiveness of foetal fibronectin (fFN) and transvaginal cervix ultrasonography in predicting successful labour induction for unfavourable cervixes (Bishop score 5 or below).
 Subjects and Methods: In the Maternity Centre, Faculty of Medicine, Ain Shams University, a prospective study was carried out. Patients in this study were selected from those attending in Obstetrics Outpatient Department who were nullipara pregnant women. 40 women were assessed for study eligibility and fulfilled all inclusion criteria.
Results: Mode of delivery had a significant correlation with Bishop score, while there was no discernible correlation between delivery method and transvaginal ultrasound. The bishop score was significantly correlated with fFN, all the cases with bishop 3 were negative fFN. The OSS showed insignificant relation with fFN. Also, there was no significant difference between negative and positive fFN regarding cervix (CX) length. The sensitivity of CX in prediction of successful labor induction occurring within 24 hours at cut off value of 3.11 was 50.0% and the specificity was 53.2%, and the accuracy was 51.1%. The Bishop score at cut off value of 4.0, the sensitivity was 60%, specificity was 64.5% and the accuracy was 62%. The sensitivity of fetal fibronectin in prediction of successful labor induction occurring within 24 hours at cutoff value 1.56 was 85%, the specificity was 80% and the accuracy was 82.6%.
Conclusion: Although transvaginal cervical length measurement provides an objective way to evaluate the cervix when the Bishop score is equivocal, it may not be able to predict failed inductions with enough accuracy but it can help identify women who are at risk for caesarean delivery. fFN showed a highly significant sensitivity, specificity and accuracy to predict the successful induction of labor .