As a psychologist specializing in sleep disorders, I hear this complaint the most from new patients: "I fall asleep okay, but I wake up during the night."
Everyone wakes up a few times per night. Cycling out of sleep roughly every 90 minutes to two hours is normal. But frequent wakings can affect physical, emotional and mental functioning. We fail to get adequate quantities of the deepest stages of sleep, and react to disruptions with metabolic, inflammatory and stress responses.