The common causes of blood red leucorrhea in 13 year olds are as follows: 1. Menstruation: 13 year olds have developed secondary sexual characteristics and will experience menstruation about 2 years thereafter. Parents need to pay attention to whether the 13-year-old child has menstruation, and also pay attention to local care and hand hygiene to prevent vaginitis. 2, vaginitis: parents need to pay attention to whether the child has local itching, whether the leucorrhea is smelly or yellow, etc. If these conditions exist, it usually indicates vaginitis, which needs to be promptly checked and treated. Therefore, a 13-year-old child with blood-red leukorrhea needs to be taken seriously and cared for. Parents need to pay attention to the cleanliness of the child’s hands and proper rest, and to strengthen the resistance to prevent local infections. In addition, they should pay attention to a light diet, consume more fruits and vegetables, eat less spicy, greasy and stimulating foods, and drink plenty of water. If the above causes are ruled out, 13-year-old children with blood-red leucorrhea should be promptly examined and treated by a pediatric gynecologist.