Binenbaum and colleagues describe the prevalence and causes of retinal hemorrhage among infants and young children in an outpatient ophthalmology clinic, testing the hypothesis that if vaccination injections cause retinal hemorrhage, then retinal hemorrhage should be seen frequently and be temporally associated with immunization. In a retrospective cohort study among 5177 children 1 to 23 months old undergoing a dilated fundus examination for any reason, excluding those with intraocular surgery or retinal neovascularization, 9 had retinal hemorrhage. All 9 had abusive head trauma diagnosed from nonocular findings. Among a subset of 2210 children with complete immunization records, 163 had an eye examination within 7 days of vaccination, 323 within 14 days, and 494 within 21 days. No children had retinal hemorrhage within 7 days of vaccination, 1 within 14 days, and none within 21 days, suggesting no temporal association between vaccination and retinal hemorrhage.