If a sexually mature woman has abdominal distension and pain, if necessary, do the relevant examination to find the cause. Second, uterine fibroids, uterine adenomyosis and other organic lesions lead to small abdominal distension and pain, accompanied mostly by a drop in the small abdomen. The diagnosis can be clarified by doing ultrasound, tumor markers, CT and other related examinations. Thirdly, ectopic pregnancy and intrauterine pregnancy with pre-eclampsia can cause abdominal pain with nausea, vomiting and other early pregnancy reactions, which can be clearly diagnosed by checking blood or urine pregnancy test and ultrasound. Fourth, urinary system infection or enteritis and other diseases, can appear the small abdominal distension and pain accompanied by frequent urination or diarrhea and other related clinical symptoms.