The dosage of radiations delivered during gynaecological brachytherapy is usually calculated for the bladder and the rectum. A new technical approach is described in order to known the dose of radiation received by the terminal portion of the ureter. During placement of the Fletcher suit one of the ureters is catheterized by a special stent which appears on the X-rays control used for dosimetry. Data of 16 pre-operative brachytherapies for carcinoma of the cervix were studied. In half of the cases, the dose debit was higher on the ureter than on the bladder and the rectum. In 7 cases, the dose delivered was also higher on the ureter rather than on the bladder and the rectum. And in 3 cases this dose was higher than 50 grays. It is concluded that the ureter is frequently the most irradiated organ in the pelvis during brachytherapy for carcinoma of the cervix. This may be a physiopathologic explanation for some ureterovaginal fistulas occurring after radical hysterectomy.