Abstract. OBJECTIVE: To describe the placental findings in asphyxiated newborns treated with hypothermia and to determine their association with the presence and severity of later brain injury. METHODS: Prospective cohort study of the placentas of asphyxiated newborns treated with hypothermia, in whom later brain injury was defined by brain imaging and/or autopsy results. RESULTS: Of the 142 asphyxiated newborns meeting the criteria for hypothermia, 73% had placenta and brain MRI/autopsy available for analysis. Fifty-one percent of these newborns developed brain injury. Sixty-five percent had microscopic placental findings involving the fetal vascular supply, which were comparable in asphyxiated newborns developing or not developing brain injury. Among the asphyxiated newborns with normal placental growth, the placental microscopic findings tended to be more common in those developing brain injury compared to those who did not: chorionic plate meconium in 50% compared to 36%, chorioamnionitis in 75% compared to 44%, and villitis of unknown etiology in 67% compared to 33%, but this did not reach statistical significance. CONCLUSIONS: Antenatal placental processes are common in term asphyxiated newborns treated with hypothermia. The placenta of each asphyxiated term newborn treated with hypothermia should be carefully examined to better understand its role in the progression from perinatal depression to brain injury.