Background: Therapeutic hypothermia (TH) improves the outcome in HIE but cvEEG is vital to detect any seizures that occur. Unfortunately, the costs associated with cvEEG can make it impractical. We studied outcomes in TH with the objective of optimizing the length of cvEEG required. Methods: Term infants with HIE were treated with 72 h of TH followed by 6 h of rewarming. cvEEG reports were quantified (background, sharp transients, seizures) and compared with pre and post-cooling variables to determine whether risk stratification was possible. Results: 25/78 infants had seizures during the TH, however, most seizures occurred early, with 7 infants seizing prior to cooling and 15 having their first seizure within 24h. Only 3 infants had their first seizure between 24-48h and none were recorded after. Novel seizures after 24h were brief and did not require treatment. EEG variables such as frequent sharp transients and first seizures within 24h were correlated with MRI abnormalities. Conclusions: For the majority of infants undergoing TH, 24h of cvEEG may be sufficient with few infants requiring longer than 48h. A combination of clinical variables (abnormal neurological exam) and EEG traits (frequency of discharges, seizures) can help to decide on the likelihood of seizures and length of EEG recording needed.