The second day of coitus bleeding bright red may be pregnant, may also be caused by other factors, there are several main reasons: 1, consider the emergence of ovulation bleeding, many women in the ovulation period due to the body’s hormone secretion imbalance, which will lead to the endometrium shedding bleeding, this is a relatively normal body situation, basically do not have to worry about it. 2, it may also be caused by the pregnancy after the implantation of the bleeding, the fertilized egg will produce some stimulation of the abdomen will have bleeding but the bleeding is relatively small, as long as the bleeding is not much, you do not have to worry about it. When the fertilized egg is placed in the abdomen, there will be some stimulation, and bleeding may occur but the amount of bleeding is relatively small, as long as the amount of bleeding is not much, you can not need to be treated. 3, there may be gynecological diseases that lead to bleeding symptoms, such as vaginitis, pelvic inflammatory disease, etc. These diseases will lead to inflammation of the body after the emergence of these diseases. These diseases can lead to increased inflammation, and the uterus will be stimulated again after intercourse, which will result in bleeding.