I kept waking up at 3 a.m. — sleep doctors pinpoint 3 reasons behind my middle insomnia and how to fix it

A dark haired woman sleeps peacefully in a white bed. Inset, a dark haired woman leans out of bed to check the clock - it's 3 a.m.

Just when I think I’ve got my sleep problems under control and I'm finally getting the rest I need, my 3 a.m. wake ups make an unwelcome return. During these periods of middle insomnia (the most common cause of insomnia) I wake with a jolt and my heart pounding in my chest.

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