Controversy exists surrounding the appropriate indications for intravenous pyelography (IVP) in assessing blunt renal injuries in children. Forty-one consecutive cases of suspected blunt renal injuries, who had an IVP performed between January 1988 and December 1990 at The Children's Hospital of Eastern Ontario, were examined by a retrospective chart review. Eighty percent of the IVPs were normal. Of the eight abnormal IVPs, four were contusions, two lacerations, and two nontraumatic abnormalities. There was no hemodynamic compromise, no requirement for surgical intervention, and no deaths in the study population. In the absence of significant hematuria (> or = 100 rbc/hpf), the probability of detecting a traumatic abnormality on IVP is low (4%). There was no correlation between the mechanism of injury and the IVP findings. We conclude that intravenous pyelography has a low yield in the absence of significant hematuria (> or = 100 rbc/hpf).