The sudden appearance of pain in the small abdomen of women is a relatively common symptom, which can occur in a variety of diseases, and needs to be analyzed according to the accompanying other symptoms as well as the woman’s menstrual history, sexual history, etc. If necessary, the diagnosis can be confirmed with the help of auxiliary tests. The reason for the pain in the abdomen is: 1, ectopic pregnancy rupture, ectopic pregnancy rupture miscarriage is one of the main causes of sudden pain symptoms in the small abdomen, usually have a normal sex life, menstrual delay does not appear suddenly occur in the lower abdomen pain symptoms, accompanied by vaginal bleeding symptoms are considered to be ectopic pregnancy rupture miscarriage. 2, acute pelvic inflammatory disease, is a common cause of pain symptoms in the lower abdomen of women, in the occurrence of symptoms in the history of childbirth, before the symptoms are not. The first thing you need to do is to have a history of childbirth, miscarriage, intrauterine evacuation or IUD placement, IUD removal, etc. If the aseptic operation is not strict or the personal hygiene habits are poor, the pathogenic microorganisms invade the infection and cause acute pelvic inflammation, which results in obvious lower abdominal pain and abnormal vaginal discharge.