The way to determine whether it is teratoma or luteal cyst is ultrasound examination, clinical manifestations and so on. 1. Ultrasound examination: ultrasound examination of teratoma, the result will appear strong echo mass, and will exist at any time of examination, will not disappear by itself; while luteal cysts will usually be in the middle and late menstruation ultrasound examination shows hypoechoic mass, but after menstruation review will disappear. 2. Clinical manifestations: most teratoma patients have no obvious symptoms in the early stage, with the growth of the tumor, patients may have abdominal pain, abdominal distension, difficulty in defecation, etc., and abdominal masses can be detected; while corpus luteum cysts are usually asymptomatic, if corpus luteum rupture occurs, lower abdominal pain, nausea, vomiting and other symptoms. It is recommended that patients go to the hospital in time, follow the doctor’s instructions for examination, and receive treatment as soon as possible after the cause of the disease has been clarified.