The term “great aunt” is generally used to refer to menstruation. A woman is usually not pregnant if she has a normal period after sex, but in the early stages of pregnancy, she may also experience vaginal bleeding, which is not a period. If pregnancy has already occurred after sex, then the uterine lining will gradually thicken to promote the development of the embryo, and menstruation will not occur. If fertilization of the egg does not occur after sex, the uterine lining will shed to form menstruation. Therefore, under normal circumstances, pregnancy does not occur when menstruation occurs. However, some people in the early stages of pregnancy will have vaginal bleeding during the previous menstrual cycle, the bleeding is relatively small, there is no symptom of back pain and abdominal pain, and it does not affect the development of the fetus, which is not menstruation. Therefore, you should take adequate precautions when having sex, conduct the necessary tests to determine whether you are pregnant, and should not base your judgment on vaginal bleeding alone, but should seek medical attention if necessary.