Shrinkage of the mass with conservative treatment of ectopic pregnancy may be due to absorption of blood in the mass or flow into the pelvis, while elevated HCG on the third day indicates that conservative treatment is not effective. Ectopic pregnancy is a pregnancy in which the gestational sac is planted outside the uterine cavity. Due to the limited nutrition and blood supply outside the uterus, it will manifest as bleeding from the gestational sac and the formation of a mass. If the mass no longer bleeds after conservative treatment, the small amount of accumulated blood in the mass may be absorbed or flow into the pelvis, then it will manifest as a shrinking mass. However, after conservative treatment of ectopic pregnancy, the effect of the treatment also needs to be evaluated in conjunction with changes in blood HCG. If the blood HCG is elevated on the third day of conservative treatment, the treatment is not effective, and if necessary, it needs to be treated again with medication or surgical treatment. Ectopic pregnancy is an abnormal pregnancy, after diagnosis, must be hospitalized in time, according to the physical condition of the doctor’s guidance to choose the appropriate treatment plan, during the treatment, closely observe the abdominal pain, vaginal bleeding.