[Transvaginal sonography in prediction of preterm delivery in patients presenting with signs and symptoms of preterm labor].
OBJECTIVE
The purpose of the study was to assess the clinical value of transvaginal sonography in the group of women presenting with preterm contractions and cervical changes.


METHODS
We prospectively evaluated 82 patients between 23-34 weeks of gestation presenting in our department with signs and symptoms of preterm labor, intact membranes and cervical dilatation < 3 cm. In all cases transvaginal sonography was performed. The following parameters were assessed: functional canal length, funneling, cervical diameter and the length of the vaginal portion of the cervix. The primary outcome was delivery < or = 28 days from examination.


RESULTS
The rate of preterm delivery (< 37 weeks) was 25.6% (21/82) and 17.1% (14/82) of the patients delivered < or = 28 days from the examination. Among the analyzed parameters, the significant difference between patients delivered < or = 28 and > 28 days from examination, was noticed only for the functional canal length (21.6 mm vs 30.1 mm; p < 0.001). The analysis of ROC curves showed that functional canal length had the highest diagnostic capability. Two important thresholds were found--20 mm and 31 mm. For predicting delivery < or = 28 days the functional canal length < or = 20 mm had sensitivity of 57.1%, specificity of 92.6%, PPV of 61.5% and NPV of 91.3%. The cutoff value of 31 mm had sensitivity of 100%, specificity of 47.1%, PPV of 28% and NPV of 100%. In multiple logistic regression analysis only FCL < or = 20 mm (OR 8.18; p = 0.027) was independently associated with PTD.


CONCLUSIONS
1. The shortening of the functional canal length (< or = 20 mm) is predictive of impending preterm delivery and the functional canal length > 31 mm is the indicator of the absence of labor. 2. Cervical sonography can be a valuable adjunct to the clinical assessment of patients with signs and symptoms of preterm labor.
Hincz
P
P
Klinika Medycyny Matczyno-Płodowej ICZMP w łodzi.
Wilczyński
J
J
Kozarzewski
M
M
Szaflik
K
K
D000328:Adult; D002584:Cervix Uteri / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007752:Obstetric Labor, Premature / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D011247:Pregnancy; D011446:Prospective Studies; D012372:ROC Curve; D012307:Risk Factors; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D016216:Ultrasonography, Prenatal / Q000379:methods; D014621:Vagina