According to the literature, sperm can survive in a woman’s body for up to 1 week, so intercourse does not have to coincide with ovulation, as long as the woman ovulates within 1 week after intercourse, there is a possibility of conception. Usually, conception requires a male sperm and a female egg, which combine in the fallopian tube to form a fertilized egg. The fertilized egg usually implants in the endometrium after 7-10 days, and after implantation, the HCG secreted by the gestational sac enters the mother’s body and is expressed as an increase in blood HCG, thus confirming pregnancy. Usually the urine pregnancy test is positive after 1 week, so the sperm can survive in the woman’s body for a longer period of time and there is no need to be too anxious. Patients should try to have intercourse on the day of ovulation or within 2-3 days before, when the vaginal secretions are alkaline and sperm are more likely to survive, so it is the best time for conception.