PIP: Reported is the first known case in which vasovenous fistula occurred as a complication of vasectomy. A 44-year-old US man, who had undergone a routine vasectomy 3 months earlier, presented with hematospermia and gross hematuria. Cytoscopy revealed blood emanating from the left ejaculatory duct. Left scrotal exploration demonstrated a vein transversing into the area of the vas deferens where previously placed clips were present. Histopathological examination revealed multiple vascular structures, abnormal in number and caliber, which were adherent to the vas deferens. It is postulated that, in this case, the hematoma occurred as a result of bleeding from a vein adjacent to the surgical clip. The inflammatory response to the clip may then have involved the neighboring injured vein, resulting in fistula formation. This rare complication can be averted through efforts not to injure vascular structures during vasectomy.