In what situations is the amount of bleeding most common?

Artificial abortion is the end of early pregnancy through surgery. In the early pregnancy vacuum suction surgery, bleeding rarely exceeds 50 ml. If the amount of bleeding during the operation exceeds 200 ml, and the amount of bleeding during the curettage exceeds 400 ml, it is called artificial abortion bleeding. The reasons for the large amount of bleeding during the operation may be: ① The gestational age is too large, the uterus is in lactation, and the number of pregnancies is multiple, the uterus is large, soft, and the contraction is poor. ② Insufficient negative pressure during suction or the suction tube is too small, the embryonic sac and decidua cannot be sucked out, the blood sinus opens, and bleeding occurs. ③ Coagulation dysfunction ④ Uterine damage. ⑤ The placenta is in a low position, and more bleeding can occur when the cervix is ​​dilated.