Vaginal rupture is a rare complication of hysterectomy. It is, among others, related to age and the incidence is higher in postmenopausal women. The rupture can occur spontaneously or in relation to clinical follow-up. In ovarian cancer the follow-up after surgery includes clinical examination, cancer antigen (CA)-125, and transabdominal and transvaginal ultrasonography. We experienced vaginal rupture in three patients with ovarian cancer. All patients had undergone surgery for ovarian cancer and were receiving chemotherapy. The rupture occurred shortly after transvaginal ultrasonography, performed by separate radiologists specialised in ultrasonography. All patients had acute surgery without any complications. Caution should be taken when performing transvaginal ultrasonography in hysterectomised patients and the complication of vaginal rupture should always be borne in mind.