Intercourse during the implantation of the fertilized egg may lead to miscarriage. During the implantation of the fertilized egg, the fertilized egg may be free in the uterine cavity. Having intercourse during this time will cause stimulation to the uterus, resulting in frequent uterine contractions, which may affect the implantation of the fertilized egg, and may easily lead to biochemical pregnancies, which may result in the failure of the woman’s pregnancy. Therefore, during the period of fertilization of the egg, couples try not to cohabit, and also to avoid strenuous exercise, pay attention to the hygiene of the lower body, wash the lower body diligently, but also to adjust the diet to ensure balanced nutrition. In the first three months after the success of the pregnancy, belonging to the early stage of pregnancy, should also avoid coitus, to avoid triggering the possibility of preterm abortion.