Is transabdominal sonography of the cervix after voiding a reliable method of cervical length assessment?
OBJECTIVE: The purpose of this study was to assess the correlation and agreement between transvagi-nal and transabdominal cervical length measurement after bladder emptying as well as the feasibility of transabdominal sonography in cervical length screening. METHODS: This was a prospective cohort study involving 287 participants (14-34 weeks’ gestation) from January to December 2003. After voiding, transabdominal and transvaginal cervical length measurements were obtained. The optimal trans-abdominal technique was established during an unblinded series of transabdominal and transvaginal cervical length measurements (n = 96). The same measurements were obtained in 191 participants under a blinded 2-sonographer protocol. The transabdominal cervical length cutoff to ensure 100% sensitivity in detecting a short cervix (