What are possible reasons that my child only has seizures while he is sleeping?

This is common: Many patients have seizures more often or exclusively in sleep. Sleep is well known to induce seizures, especially in children. Some seizures, such as centro-temporal seizures, occur almost exclusively in sleep. Also, sleep apnea can drastically reduce oxygen levels and therefore induce seizures.

Sz: It is not entirely one reason or even completely understood. But sleep is generated and processed through deep structures of the brain, and so are seizures despite originating from an irritable or electrically hyper excitable brain. When we transition into and out of sleep, the electrochemistry of our brain is much more susceptible to that irritability which could trigger a seizure.