If bleeding occurs after the 7th day of transplantation, the following possibilities are considered: 1. Failure of embryonic development or pre-eclampsia miscarriage. In this case, the patient needs to check the blood HCG and progesterone, if the result is relatively good, it is considered to be pre-eclampsia, and timely fertility treatment can be carried out according to the situation; if the result is not good, it is considered to be a failure of embryo implantation and the possibility of miscarriage is higher. 2. The possibility of ectopic pregnancy. In this case, dynamic observation of blood hHCG and progesterone and ultrasound is needed. If ectopic pregnancy is diagnosed, timely drug conservative treatment or surgery is needed to avoid the risk of rupture. 3. Consider bleeding caused by possible cervical lesions or vaginal changes. After pregnancy, the vaginal resistance gradually decreases and the vagina becomes locally congested. If the patient has inflammatory diseases of the vagina or cervical polyps, bleeding can occur.