The reliability of transvaginal ultrasonography to detect retained tissue after spontaneous first-trimester abortion, clinically thought to be complete.

In order to assess the reliability of transvaginal ultrasonography for the detection of trophoblastic tissue retained after spontaneous first-trimester abortion and clinically thought to be complete, the clinical, sonographic and pathological data of 33 women were retrospectively analyzed. The patients' mean age was 34 years (range 24-48). The mean gestational age at presentation of symptoms was 8 weeks (range 5.1-11.1). Transvaginal sonography showed that in 18 cases retained tissue was absent, and that in 15 patients, retained trophoblastic tissue was suspected. Pathological reports (following dilatation and curettage) confirmed the absence of retained tissue in 17 cases and demonstrated its presence in 16 patients (13 in whom retained tissue was suspected by sonography and three in whom retained tissue was not suspected). Sensitivity, specificity, positive predictive value and negative predictive value in our series were 81%, 94%, 93% and 83%, respectively for the detection of retained trophoblastic tissue. We conclude that transvaginal ultrasonography is a reliable method to detect the presence of retained trophoblastic tissue following spontaneous first-trimester abortion, clinically thought to be complete.