What causes birthmarks on baby faces?

Baby long birthmark, on the one hand, the internal factor is the baby in the process of pregnancy for some colored hormone precipitation birthmark, including blood, body fluids, etc., the second is the external factor, including the baby in the process of pregnancy a certain part of the long-term extrusion and other external factors, is the formation of pigment deposition birthmark, can be processed according to the baby's situation. After the baby is born, prevent the baby from keeping a posture for a long time to sleep. If the birthmark on the baby's face is particularly obvious, you can choose the treatment method to reduce it. At ordinary times, you must pay attention to the baby's skin care and pay attention to keeping the baby's skin clean.