Diagnosis of pregnancy-associated uterine venous plexus thrombosis on the basis of transvaginal sonography.

Objective. To describe the sonographic signs of uterine venous plexus thrombosis. Methods. Four pregnant patients had a diagnosis of uterine venous plexus thrombosis in the first half of gestation. The diagnosis was based on transvaginal sonography only in 3 cases, and the fourth had magnetic resonance imaging corroboration. Results. All 4 patients had similar sonographic features of uterine venous plexus thrombosis on transvaginal sonographic examination. The thrombi within the dilated veins were shown as elongated echogenic structures along the lumen that appeared round on transverse views of the affected veins. They showed swinging movements provoked by gentle transducer pressure. Power and color Doppler sonography enhanced the uterine venous plexus thrombosis diagnosis by showing blood flow around the thrombi. There were no signs of thromboembolic disease. Sonographic findings in deep leg veins and iliac veins were normal in all cases. Complete thrombophilia studies did not reveal any abnormalities. The uterine venous plexus thrombosis could not be detected on transabdominal sonography and was shown better by transvaginal sonography compared with magnetic resonance imaging. During 3 months of anticoagulation therapy, the thrombi gradually disappeared in all cases. Conclusions. Focusing on the pelvic veins while performing a transvaginal sonographic study during pregnancy may reveal important findings, which may have clinical implications. The therapeutic treatment of uterine venous plexus thrombosis is controversial and still empirical.