There are differences in the time of onset, cause, management and final outcome between preeclamptic abortion and biochemical pregnancy. 1. Time of occurrence: Pre-eclampsia occurs after the fertilized egg has been deposited in the uterine cavity, while biochemical pregnancy occurs after the sperm and egg have united to become a fertilized egg, and miscarriage occurs before the egg has been deposited in the uterine cavity. 2. Causes: Pre-eclampsia is caused by the quality of the fertilized egg itself or the stimulation of the pregnant woman, while biochemical pregnancy is caused by the problem of the sperm or egg or the environment of the uterine cavity which is not suitable for the implantation of the egg. 3. Treatment: Pre-eclampsia usually needs to be treated according to the condition of the fetus and the pregnant woman to decide whether to continue the fertility preservation treatment, while biochemical pregnancy does not need treatment, just like a normal menstruation. 4. Final outcome: part of the preeclampsia can continue the pregnancy and the fetus can survive through active fertility preservation treatment. But in biochemical pregnancy, the fertilized egg has not been attached to the bed, there is no possibility of continuing the pregnancy.