Digital examination and transperineal ultrasonographic measurement of cervical length to assess risk of preterm delivery

Objective: To compare the diagnostic performance of cervical length measurement determined with transperineal ultrasonography and digital assessment of the cervix for the prediction of preterm delivery in patients with preterm labor. Method: 90 patients admitted to the hospital with the diagnosis of preterm labor and intact membrane underwent cervical length measurement by transperineal ultrasonography along with digital examination for cervical dilatation and effacement. The main outcome measure was delivery before 37 weeks' gestation. Results: 32 patients (35.5%) delivered preterm. Receiver operative characteristic curve analysis revealed that cervical canal length less than or equal to 28 mm measured by transperineal sonography had the highest diagnostic performance with a sensitivity of 78.1% and specificity of 82.7%. The sensitivity and specificity of digital examination were found to be 65.5%, 72.4% and 62.5%, 68.9% for the cervical dilatation > 2 cm and effacement greater than or equal to 40%, respectively. Conclusion: Transperineal ultrasonographic examination for cervical length is more accurate than digital examination for prediction of preterm delivery in patients presenting with preterm labor. Transperineal ultrasonographic examination of cervix is invaluable in the prediction of preterm delivery where transvaginal transducers are lacking or skilled staff. are unavailable. (C) 1997 International Federation of Gynecology and Obstetrics.