Transvaginal ultrasonography examination of the uterine cervix in hospitalised women undergoing preterm labour.
OBJECTIVE
Our purpose was to assess the accuracy of cervical mensuration (length, wedging) by transvaginal ultrasonography in the prediction of preterm birth among hospitalised women undergoing preterm labour.


METHODS
Evidence was extracted from articles through a MEDLINE search from 1987 to 1997, followed up by examining the references at the end of pertinent articles. The key words were: pregnancy, cervix, ultrasonography, preterm labour, preterm delivery, cervical length, cervical wedging or funnelling. Final criteria for the selection of the studies were cervical length and/or wedging at internal os in hospitalised women undergoing preterm labour without restriction on the study design.


RESULTS
Nine articles from 12 publications were analysed and incorporated in a discussion. Study design and selection criteria vary among publications. Preterm delivery was the principal outcome, but its definition is not the same according to the authors. The best cut-off for cervical length varies from 18 to 30 mm. The size of the samples is limited. The sensitivity for predicting preterm birth ranges from 68 to 100%, and the specificity ranges from 30 to 78%. Cervical wedging has a sensitivity varying from 23 to 100%, and a specificity ranging from 54 to 90%.


CONCLUSIONS
Ultrasonography of the cervix is an interesting technology as it is cheap and easy to use. However this technique remains to be assessed before implementing it in daily clinical practice. Finally, studies incorporating transvaginal ultrasonography into interventional trials are needed to determine the efficacy of measuring cervical length in the prevention of preterm birth.
Vendittelli
F
F
Service de Gynécologie-Obstétrique, CHRU de Pointe-à-Pitre, 97159, Pointe-à-Pitre, Guadeloupe.
Voluménie
J
J
D002584:Cervix Uteri / Q000000981:diagnostic imaging* / Q000502:physiology; D005260:Female; D006761:Hospitals; D006801:Humans; D007752:Obstetric Labor, Premature / Q000150:complications / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D011247:Pregnancy; D014463:Ultrasonography / Q000379:methods; D014592:Uterine Hemorrhage / Q000150:complications; D014621:Vagina