The formal medical term for great aunt is menstruation. It is usually possible to distinguish whether it is a menstrual or ectopic pregnancy by ultrasound, but it is also necessary to determine this in conjunction with blood HCG and a history of menopause. First of all, when a woman has an ectopic pregnancy, an ultrasound may show the gestational sac outside the uterine cavity, whereas an ultrasound during menstruation can only show the separation of the uterine cavity, with no abnormal changes outside the uterine cavity. However, if the pregnancy is still short, ultrasound examination may not see the gestational sac, there will be errors, but also need to be combined with the history of menopause and blood HCG test to determine. Menstruation is usually regular and close to the usual menstrual period, but ectopic pregnancy bleeding will have a clear history of menopause, delayed menstruation for more than a week, followed by vaginal bleeding and abdominal pain and discomfort and other symptoms. Ectopic pregnancy examination blood HCG value is elevated, the blood HCG value will not be elevated when menstruation. The history of menopause, ultrasound and blood HCG test can usually distinguish between menstruation and ectopic pregnancy bleeding.