Sitting with a foreign body sensation in the abdomen, may be related to obesity, constipation, urinary retention, pelvic inflammatory disease and other conditions. 1. Obesity: If the patient is overweight, the fat content of the abdomen is more, when sitting, the abdominal flab will be piled up together, forming a pile, squeezing the patient’s stomach or chest, so that the patient feels a foreign body sensation. 2. Constipation: If the patient has not pooped for a long time, the fecal tissue will accumulate in the intestines, when the patient sits, the pressure brought by the fecal tissue will make the patient feel that there is a foreign body sensation in the abdomen, usually after defecation, the foreign body sensation will disappear. 3. Urinary retention: if the patient has difficulty urinating, urination is not complete, and a large amount of urine accumulates in the bladder, there will be a foreign body sensation in the abdomen while sitting. 4. Pelvic inflammatory disease: If a woman has pelvic inflammatory disease, the inflammation can stimulate the pelvic organs or the pelvic peritoneum, and there is a foreign body sensation in the abdomen. Due to the complexity of the etiology, it is recommended that patients actively seek medical attention to clarify the cause of the disease.