Prediction of delivery within 7 days after ultrasonographic measurement of the cervical angle and cervical length in term pregnancies

Kim, Gwang Jun

Abstract

OBJECTIVE
The study was to assess the value of the cervical angle (CA) and cervical length (CL) measurement by transvaginal ultrasonography (USG) in predicting delivery within 7 days after USG in low risk singleton term pregnancies.
METHODS
This prospective study included 85 singleton low risk term pregnancies. The CA and the CL were measured at 36 weeks' gestation and each week thereafter. Seven cases were lost to follow-up and finally a total of 78 cases were analyzed. The number of days to delivery was recorded. The odds ratios of the CA and CL for predicting delivery within 7 days after USG at different weeks' gestation were calculated using the Cox proportional hazard model. Receiver-operation characteristic curves were drawn to determine the cutoff values of the CA and CL.
RESULTS
CA measurement did not predict delivery within 7 days after USG. However, there was a significant relationship between the CL and the days to delivery at 37 weeks' gestation. The optimal cutoff value in predicting the delivery within 7 days was 10 mm at 37 weeks' gestation. We could not obtain proper cutoff points at other weeks' gestation.
CONCLUSION
CA measurement by transvaginal USG may not have a significant clinical impact on predicting delivery within 7 days after USG. However, CL measurement USG at 37 weeks' gestation can help predict the delivery within 7 days after USG.