[Vaginal sonography as a method of study in the evaluation of cervix insufficiency. A useful complement to vaginal palpation?].

In a clinical study a group of pregnant women with suspected cervical incompetence was examined by vaginal sonography. Aim of the investigation was to compare results of performed vaginal palpation with results of sonography. 53 pregnant women between 20th und 31st week of gestation were examined by a 5 MHz vaginal sector-scanner probe. After focussing sagittal projection of uterine cervix and lower uterine segment the cervical length and opening of the internal os were assessed prior to cerclage. Postoperative vaginal sonography was performed to ascertain lengthening and stabilization of the incompetent cervix. Comparing results of vaginal palpation and vaginal sonography showed, that the cervical length obtained by sonography was constantly higher in all patients than the results obtained by palpation. This difference became more distinct in the group of patients with extreme cervical incompetence. We are of the opinion that vaginal sonography is an objective method revealing the extent of cervical incompetence. Exact measurement of the cervical length and assessment of the internal os are efficient diagnostic criteria. They complete results of cervical palpation and offer precise information concerning an intended cerclage.