Perinatal hypoxia is a significant cause of brain injury in preterm infants. Neuroprotective treatments have proven beneficial when commenced within 6-8 hours post hypoxic-ischemic insult. However, as the exact time of injury is unknown, there are no current means to determine which infants are in the treatment phase of the evolving injury. Recent studies suggest epileptiform transients in the first 6-8 hours are predictive of outcome. To quantify this further an automated means of transient identification is required. In this paper we describe a method using Haar wavelets to detect spikes in the preterm fetal sheep EEG after asphyxia in utero. The method exhibits good sensitivity and selectivity over 3 specific time periods and demonstrates the feasibility of using wavelets for spike detection in fetal sheep.