Initial management of intussusception is enema reduction. Data are scarce on predicting which patients are unlikely to have a successful reduction. Therefore, we reviewed our experience to identify factors predictive of enema failure.A retrospective review of all episodes of intussusception over the past 10 years was conducted. Demographics, presentation variables, colonic extent of intussusceptions, and hospital course were collected. Extent of intussusception was classified as right, transverse, descending, and rectosigmoid. Episodes were grouped as success or failure of enema reduction and compared using the Student t test for continuous variables and χ 2 test for dichotomous variables. Significance was P less than .05.We identified 405 episodes of intussusception and 371 attempts at enema reduction. There were 285 successful enema reductions. There was no difference between groups in age; sex; or the presence of emesis, fever, or abdominal mass. The failed enema group was more likely to have had symptoms over 24 hours before presentation (P = .006), bloody diarrhea (P < .001), and lethargy (P < .001). The chance of success diminished with colonic extent (right, 88%; transverse, 73%; left, 43%; colorectal, 29%; P < .001).Predictors of failed enema reduction of intussusception include presence of symptoms over 24 hours, diarrhea, lethargy, and distal extent of intussusception.