The aim of the study was to determine whether transabdominal ultrasonography can accurately identify paravaginal defects associated with genuine stress urinary incontinence. Sixteen women were diagnosed with genuine stress urinary incontinence (GSUI) following clinical evaluation, urethroscopy and urodynamic studies. They were then evaluated by transabdominal sonography and a full bladder and immediately following micturition. The ultrasound studies were also carried out in 8 women (5 nulliparous and 3 primiparous) who had no signs or symptoms of urinary incontinence. Paravaginal defects were detected in the 16 women with GSUI: 9 had unilateral defects and 7 had bilateral defects. Only right-sided defects were identified in women with unilateral lesions. Paravaginal defects were confirmed in all symptomatic women at the time of surgery, and corresponded with the defects identified with transabdominal ultrasound. Mild unilateral paravaginal defects were identified in 2 continent parous women. Five nulliparous women and 1 primiparous control had no ultrasound evidence of paravaginal defects. A transabdominal, transverse, suprapubic ultrasound scan with a full bladder is a promising screening technique for the diagnosis of paravaginal defect in women with GSUI. Transabdominal suprapubic longitudinal sections are not useful for the identification of paravaginal defects.