OBJECTIVE: Hypoxic-ischemic encephalopathy (HIE) is a major cause of perinatal brain injury. Creatine is a dietary supplement that can increase intracellular phosphocreatine to improve the provision of intracellular adenosine triphosphate (ATP) to meet the increase in metabolic demand of oxygen deprivation. Here, we assessed prophylactic fetal creatine supplementation in reducing acute asphyxia-induced seizures, disordered electroencephalography (EEG) activity and cerebral inflammation and cell death histopathology. METHODS: Fetal sheep (118 ± 1 days' gestational age [dGA]; 0.8 gestation) were implanted with electrodes to continuously record EEG and nuchal electromyogram activity. At 121 dGA, fetuses were randomly assigned to sham control (i.v. saline infusion without umbilical cord occlusion [UCO]; SalCon), continuous i.v. creatine infusion (6 mg/kg/h; CrUCO) or isovolumetric saline (SalUCO) followed by UCO at 128 ± 2 dGA that lasted until the mean arterial blood pressure reached 19 mmHg. Brain tissue was collected for histopathology after 72 hours of recovery. RESULTS: Creatine supplementation had no effects on basal systemic or neurological physiology. UCO duration did not differ between CrUCO and SalUCO. After reperfusion, CrUCO fetuses had improved EEG power and frequency recovery and reduced electrographic seizure incidence (SalUCO, 86% vs CrUCO, 29%) and burden. At 72 hours after UCO, cell death in the cerebral cortex and astrogliosis in the periventricular white matter were reduced in CrUCO fetuses compared with SalUCO. INTERPRETATION: Creatine supplementation reduced post-asphyxial seizures and improved EEG recovery. Improvements in functional recovery with creatine were associated with regional reductions in cell death and astrogliosis. Prophylactic creatine treatment has the potential to mitigate functional indices of HIE in the late gestation fetal brain. ANN NEUROL 2025;97:673-687.