A bad doubling of HCG is considered to be caused by the gestational sac not developing well. If there is a fetal heartbeat, you should pay attention to observe whether the fetal heartbeat is normal, and you should also pay attention to the blood test of HCG and progesterone. If the progesterone level decreases or the HCG continues to decrease during this period, there is a possibility of preterm miscarriage and you should try to preserve the pregnancy. Either dextran or progesterone can be used to promote the development of chorionic gonadotropin, which has a fetal preservation effect. During the period of medication, you should pay attention to review the HCG value. If the HCG value rises steadily and the fetal heart develops well, you can rest assured that the pregnancy can be maintained and pay attention to the Down’s syndrome screening and 4D examination, and if there is no problem, the pregnancy can be continued. However, if you do the 4D examination and find that the fetus has abnormal status, it is better not to keep it, otherwise it will have a bad impact on eugenics and eugenics.