Waking up in bed with numbness in the hands may be related to physiological factors such as improper sleeping posture, may also be due to cervical spondylosis, acute cerebrovascular disease and other causes. 1. Physiological factors: if you sleep for a long time to maintain an inappropriate sleeping posture, resulting in prolonged arm pressure, resulting in blood circulation in the arm area is affected, may cause waking up hand numbness, which is a normal physiological phenomenon, when the position is changed, the symptom will disappear on its own. 2. Cervical spondylosis: the disease can lead to patients with normal physiological curvature of the cervical spine changes, and patients sleep if the pillow height is not appropriate, or sleeping posture is not correct, may lead to local nerve root pressure, resulting in sleep waking up numbness of the hands, but also may be accompanied by upper limb weakness, neck pain and other symptoms. 3. Insufficient cerebral blood supply: for patients with intracranial and extracranial vascular stenosis or occlusion, blood flow slows down significantly during sleep, resulting in insufficient blood supply and oxygenation of brain tissue, which may cause numbness of the hands when waking up from sleep. Waking up with numb hands may also be caused by other reasons, if the symptoms continue to be unable to alleviate, you should seek medical treatment as soon as possible to give targeted treatment.