If the woman’s egg has been expelled by the time the man and woman have intercourse, the fertilized egg will usually be in bed about 7 days after intercourse and a blood HCG test will be able to detect pregnancy. Therefore, pregnancy can be detected on the thirteenth day after intercourse, but you have to go to the hospital to check the blood HCG, while the early pregnancy test or pregnancy test may not be able to detect it. If a woman has not ovulated at the time of intercourse, but ovulates on the thirteenth day after intercourse, pregnancy can only be detected by blood HCG on the thirteenth day after intercourse, but not by early pregnancy test or pregnancy test, which is usually possible only about 16 days after intercourse. It is only at this time that the blood HCG will be checked later than if you had intercourse on the day of ovulation, and the HCG measured will be lower.