Ectopic pregnancy can be detected as early as about 40 days of pregnancy because in the very early stages of pregnancy, the fertilized egg is still in the process of transport in the fallopian tube or has just been laid, which is not easily visible by ultrasound because of its small size. If the gestational sac cannot be seen in the uterus, but the mass can be seen outside the uterus, such as in the abdomen of the fallopian tube or in the isthmus, the initial diagnosis of intrauterine pregnancy or ectopic pregnancy can be made by monitoring the change in blood HCG level. Once diagnosed, ectopic pregnancy is considered more likely and most of them require early surgical treatment to prevent rupture of the ectopic pregnancy. After surgical treatment, the diagnosis of ectopic pregnancy can be confirmed if the mass is removed and sent for pathological examination and if the villi can be found.