Blinded comparison of cervical portio length measurements by digital examination vs Cervilenz

Objective

Cervical length (CL) examinations may identify patients in preterm labor or those who may benefit from prophylactic therapy. We sought to compare the accuracy of clinician digital CL examinations with objective measurements using the Cervilenz device in women presenting with symptoms of preterm labor.

Study Design

Forty-two patients with singleton gestation from 24 to 34 weeks' gestation and cervical dilation less than 3 cm underwent speculum examination and Cervilenz measurement. A second examiner, blinded to results, digitally measured CL. Pearson's correlation coefficient, Student t tests and McNemar's tests were used to compare digital and Cervilenz measures.

Results

Digital CL was significantly less than Cervilenz (2.88 vs 3.40 cm; P < .001), and in 36% of subjects, this difference exceeded 1 cm. The discrepancy in CL estimates persisted whether women were multiparous or had soft cervices or a history of preterm delivery.

Conclusion

Digital assessment underestimates CL, whereas the Cervilenz device permits a visualized and objective CL measure in patients with preterm labor.

Key words: cervical length, Cervilenz, preterm labor, vaginal examination