Sleeping for a long time after the waist was wooden numbness wake up to consider physiological reasons, lumbar disc herniation, gluteal epithelial nerve compression syndrome. 1. Physiological reasons: if the night sleep lumbar cold can cause local blood circulation is not good, numbness. If the bed is too soft, the lumbar posture is poor or twisted, the lumbar load increases, and the nerve is compressed and numbness occurs. 2. Lumbar disc herniation: if you lie down for a long time, the pressure on the nerves in the lumbar region increases and numbness occurs, and the pain and numbness in the lower limbs. 3. Pudendal nerve compression syndrome: due to strain or trauma caused by the pudendal nerve compression, lumbar, hip, thigh pain and numbness. So sleep at night waist was wooden numbness wake up if the numbness persists without relief go to the hospital to check.