Significance of Gray-Level Histogram of the Uterine Cervix as a Predictor of Preterm Birth in Pregnant Women with Preterm Labor

Abstract

PURPOSE: The aim of this study was to determine the value of a gray-level histogram of the cervix as a predictor of preterm birth in women who admitted for preterm labor. METHODS: Ninety-seven women who admitted Chonnam national university for preterm labor were enrolled in this prospective study. A transvaginal ultrasonography for measurement of cervical length (CL), gray-scale histogram and cervical volume was performed when patients were admitted. Anterior and posterior cervical walls and AP (anterior and posterior) difference in MGL (mean gray level between anterior and posterior) were checked. And we analyzed the relationship between the value and preterm birth. RESULTS: The overall rate of preterm birth before 37 weeks was 53.6% and after 37 weeks was 46.4%, respectively. Logistic regression analysis demonstrated that not only cervix length (P=0.003; odds ratio [OR], 0.189; 95% confidence interval [CI], 0.064-0.560) but also anterior histogram (P=0.028; OR, 0.319; 95% CI, 0.115-0.884) was independent predictor of preterm birth before 37 weeks. The receiver operator characteristics (ROC) curves were analyzed for the anterior histogram, a value of 85.9 was the best cut-off value to determine the preterm birth. The areas under the ROC curve indicate that the variable provides a prognostic value for the prediction for preterm birth. To predict a preterm birth, anterior histogram had 78.8% sensitivity and 46.7% specificity. CONCLUSION: Gray-level histogram of the uterine cervix may predict the preterm birth in pregnant women with preterm labor.