1, within one week of birth, the coagulation function of the newborn is not yet sound, the plasma prothrombin and coagulation factor function is low, and there is a physiological decline in coagulation factors, coupled with the incomplete development of the elastic fibers of the blood vessel wall, the fragility of the vessel wall, a variety of bleeding conditions are more common. 2, eye: eyelid / orbit / subconjunctival hemorrhage, retinal hemorrhage … …retinal hemorrhage is mostly oozing or punctate hemorrhage, the amount of hemorrhage is often small but the hemorrhage is widespread and scattered, and in severe cases, it can cause a large area of hemorrhage. 3, intracranial pressure and thoracic pressure increase resulting in increased retinal venous pressure, blood return obstruction and neonatal coagulation insufficiency, blood vessel wall development is related.