It is generally not recommended to have intercourse during the implantation of the fertilized egg, which may cause miscarriage, infection and so on. 1. Miscarriage: too strenuous, too frequent sex may affect the fertilization of the egg, due to the fertilization of the egg is not stable, at this time coitus may lead to vaginal bleeding, abdominal pain and other symptoms, serious cases may cause miscarriage. 2. Infection: During coitus, external pathogens may cause upward infections, which in severe cases may lead to reproductive tract infections, such as vaginitis, cervicitis or uterine cavity infections, which may also lead to miscarriage. Therefore, it is recommended not to have intercourse during the fertilization of the egg. Fertilized eggs need a certain amount of time, usually about 7 days, during which time if there is vaginal bleeding, abdominal pain, etc., it is recommended to consult a doctor in a timely manner, under the guidance of the doctor, improve the relevant examination, to clarify the cause of the disease, symptomatic treatment.