A lot of grooves in the front and back of the stool are generally considered to be related to intestinal polyps, intestinal tumors, or hemorrhoids and other diseases. 1. Intestinal polyps: If there are polyps in the intestines, including colon polyps and rectal polyps, they may cause obstacles to the passage of feces through the intestines produced by the polyps, resulting in changes in the shape of the stool. 2. Intestinal tumors: If there are tumors in the intestines, the obstacles caused by the tumor site may cause the stool to produce grooves, and may even cause mucus blood in the stool. 3. Hemorrhoids: hemorrhoid patients generally have venous mass in the perianal area, which can easily lead to the passage of stool to be squeezed, and then cause stool shape abnormality. The first part of the stool is normal after a lot of grooves patients, it is recommended to consult a doctor in a timely manner, improve the examination, clarify the cause and diagnosis, under the guidance of a professional physician active treatment.