Sleeping hiccups may be related to cold abdomen, autonomic dysfunction, chronic gastric diseases and other factors. 1. Cold abdomen: when the abdomen is cold during sleep, the cold air stimulates the diaphragm and causes diaphragmatic spasm, which leads to hiccups during sleep. 2. Autonomic dysfunction: there may be vagus nerve dysfunction during sleep, leading to nervous system dysfunction, which leads to the phenomenon of hiccups, which may be accompanied by acid reflux, heartburn, abdominal distension and other phenomena. 3. chronic gastric diseases: such as chronic gastritis, chronic gastric ulcer, reflux esophagitis, gastric tumors, etc., these chronic gastric disease patients may have increased secretion of gastric acid at night, stimulating the gastric smooth muscle, so that its contraction spasm, the diaphragm and the stomach adjacent to the gastric contraction spasm of the gastric smooth muscle, which affects the diaphragm, the phenomenon of hiccups. Sleep hiccups may also have other pathological factors, it is recommended to go to the hospital as soon as possible to find out the cause and active treatment.