A stomach that suddenly becomes super large can be caused by pregnancy, fluid in the abdomen, bloating in the digestive tract, and abdominal masses. 1. Pregnancy: If you are a woman, you should consider whether pregnancy is the cause of the sudden enlargement of your stomach. It is recommended to buy a pregnancy test at the pharmacy or go to the hospital for an ultrasound examination of the abdominal and pelvic cavity. 2. Fluid buildup in the abdominal cavity: If there is a lot of fluid in the abdominal cavity, it can cause the stomach to suddenly get bigger. It is usually caused by liver diseases, such as viral hepatitis, which can develop into cirrhosis if it is not cured repeatedly. 3. Flatulence of the digestive tract: If there is too much gas in the gastrointestinal tract, it will cause more obvious bulging of the stomach and intestines, and thus the stomach will suddenly become bigger. 4. Abdominal mass: If the abdominal mass grows too fast, the stomach will also become bigger suddenly. It is recommended that the patient go to the hospital as soon as possible for examination and actively cooperate with the doctor for treatment, so as not to delay the aggravation of the condition.