Blood clots in the placenta may be induced by factors such as placenta hypoplasia and rupture of placental vessels. 1. Placenta hypoplasia: if the position of placenta is relatively low, close to the cervical opening, once the pregnant woman’s activity is too large, it will lead to direct stimulation of the placenta and cause hemorrhage symptoms, resulting in blood clots, and once there is a long period of blood clots, it will lead to the stimulation of the placenta and cause preterm miscarriage or premature labor. 2. Placental blood vessel rupture: it may be due to trauma or other factors that cause rupture of the capillaries of the placenta, which in turn causes bleeding and blood clots, and may lead to placental abruption or even fetal death in the womb. It is recommended to go to the regular hospital as soon as possible to receive examination, according to the relevant examination results, under the guidance of specialists to actively accept the treatment, to avoid affecting their own health and the growth and development of the fetus.