Behavioral episodes in NREM parasomniacs mostly take place after an awakening from deep sleep. Little is known about the relation between deep sleep bout duration and whether or not a patient awakes from deep sleep, either with or without behavior. We analyzed deep sleep durations from polysomnography recordings of 46 parasomniacs and 79 healthy controls. It was found that the probability of waking up from deep sleep increases, and transitioning to Non-REM2 decreases, with deep sleep bout duration. This effect was found to be larger in the parasomnia group than for the controls.