Objectives: We evaluated the value of hydrosonography in screening for intracavitary pathologies in infertile patients. Methods: A total of 93 infertile women with suspected intracavitary lesions on transvaginal ultrasonography (TVS) underwent hydrosonography. Specimens obtained either by dilatation and curettage or hysteroscopic resection were compared with findings on TVS and hydrosonography. Results: Pathology confirmed the presence of sonographically diagnosed intracavitary lesions in 40 out of 66 (60%) women. The sensitivity, specificity, positive predictive value, and negative predictive value of TVS for the detection of endometrial cavity lesions were 78%, 38%, 61%, and 59%, respectively. Forty-six out of 71 (65%) women who were found to have intracavitary lesions on hydrosonography were pathologically confirmed. The sensitivity, specificity, positive and negative predictive value of hydrosonography in the detection of endometrial cavity lesions were 90%, 40%, 65%, and 77%, respectively. Conclusions: Hydrosonography is a useful procedure in screening for intracavitary pathologies and allows differentiation of intracavitary, endometrial, and submucosal abnormalities. © 2004 International Federation of Gynegology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.