The value of transvaginal ultrasonographic examination of the uterine cervix in predicting preterm delivery for pregnant women with threatened preterm labor

Objective: To evaluate the value of transvaginal ultrasonographic examination of the uterine cervix in predicting preterm delivery for pregnant women with threatened preterm labor.Methods: Transvaginal ultrasonographic(TVS) was performed in 189 women with threatened preterm labor.Cervical parameters of the ultrasonography were evaluated including cervical length,the presence of funneling,funnel length,funnel width and cervical indexs [(Funnel length +1)/Cervical length].Results: The prevalence of preterm delivery was 34.4%(65/189) in 189 women with threatened preterm labor.A significant association was indicated by logistic regression analysis between the occurrence of preterm delivery and ultrasonographic cervical parameters.But of all ultrasonographic parameters the cervical length were the best predictor of preterm delivery.Receiver operating characteristic curve(ROC) analyses showed that a cervical length of 25 mm was the optimal cut-off to predict the perterm delivery occurrence,the sensitivity,specificity,positive predictive value(PPV) and negative predictive value(NPV) were 67.7%,75.0%,58.7%,81.6%respectively.Conclusion: It is suggested that the transvaginal ultrasonographic measurement of the uterine cervix is an objective and accurate method in predicting preterm delivery for pregnant women with threatened preterm labor.