If there is a sudden increase in weight accompanied by abdominal enlargement, it may be due to pregnancy, caused by the growth and development of the fetus in the uterus, long-term overeating, bad habits lead to overnutrition, fat accumulation, which can also cause a sudden increase in weight and abdominal enlargement. Ascites may be caused by disease, leading to sudden weight gain and abdominal enlargement, and cirrhosis of the liver may also cause abdominal enlargement. If there is endocrine disorders may be due to hormone secretion disorders in the body resulting in obesity, sudden weight gain, abdominal enlargement, if accompanied by small limbs, may be suffering from Cushing’s syndrome caused by abdominal enlargement, weight gain.