Clinically, generally the blood HCG value and vaginal ultrasound combined diagnosis, when the blood HCG>2000iu/l, vaginal ultrasound did not detect the intrauterine fetal sac, the diagnosis of ectopic pregnancy is basically established. Ectopic pregnancy, medically known as ectopic pregnancy, that is, the fertilized egg in the uterus outside the body cavity of the bed; HCG, the full name is human chorionic gonadotropin, in the 10-14 days after the conception of the placenta chorionic villous membrane of the congenital trophoblast cells began to secrete, is the diagnosis of the most sensitive method of early pregnancy, which can maintain menstrual luteal lifespan, so that it enlarges the gestational luteal, increase the secretion of steroid hormones in order to maintain pregnancy. After miscarriage or rupture of ectopic pregnancy occurs, diagnosis is mostly without difficulty; in the early stage of ectopic pregnancy, due to the clinical manifestations are not obvious, clinically, auxiliary examination is mainly used to confirm the diagnosis, such as blood HCG measurement, vaginal ultrasonography, etc.; blood HCG measurement is crucial for the early diagnosis of ectopic pregnancy. In a word, the HCG level of ectopic pregnancy patients is lower than that of normal intrauterine pregnancy; clinically, it is difficult for us to judge ectopic pregnancy based on a certain blood HCG value, in other words, there is no certain standard of HCG value of ectopic pregnancy. In other words, there is no standardized HCG value. Generally, we need to continuously monitor the patient’s blood HCG value dynamically, if the doubling time is more than 7 days, the possibility of ectopic pregnancy is very high (the doctor suggests to recheck the blood HCG value after one week, if the rechecking result suggests that the increase of blood HCG value is more than double, ectopic pregnancy will be considered); if the doubling time is less than 1.4 days, the possibility of ectopic pregnancy is very low (if the rechecking result suggests that the increase of blood HCG value is less than 1.4 days, ectopic pregnancy is basically not considered). Ectopic pregnancy). To summarize, the value obtained from a single measurement of blood HCG cannot determine whether it is an ectopic pregnancy or not. Continuous monitoring of blood HCG level and vaginal ultrasonography are needed to determine whether it is an ectopic pregnancy or not.