Pregnancy can usually be detected by blood draw 7-10 days after sex, and can be detected by urine test after another week, but it may be delayed, so it is more accurate to conduct the test one week after menopause. After sex the sperm and egg combine to form a fertilized egg, which will implant in the uterine cavity 6-7 days after its formation. HCG is produced in the blood shortly after implantation, so a blood test 7-10 days after sexual intercourse will show an elevated level of HCG. About a week later, HCG in the urine also rises, and pregnancy can be detected in the urine. However, due to individual differences, not all women can detect pregnancy at this time, and the test may be delayed, resulting in a false-negative result. Therefore, it is recommended to check for pregnancy one week after menopause.