There are many reasons for the stabbing pain in the left lower abdomen, simple pelvic inflammatory disease, pelvic infection can appear obvious pinprick-like pain, and even accompanied by pain in urination, mainly in female patients occur more often, and retrograde infection related. In the acute stage, anti-infective treatment should be chosen. In addition, for the intestinal inflammatory diseases, such as ulcerative colitis, because it mainly occurs in the rectum and the sigmoid colon, so it can be manifested as the left side of the lower abdominal pain, there will be pins and needles feeling, and also accompanied by obvious diarrhea and defecation of blood, repeated episodes of weight loss will occur. Regular colonoscopy should be carried out, and anti-inflammatory treatment should be carried out systematically, and diet and nutrition should be increased appropriately. In other cases, it is caused by simple gastroenteritis, which is related to eating, and is easily triggered after eating unclean diet, and will also have obvious digestive reactions, such as nausea, vomiting and so on.