Ovulation on the 8th day of sex is the possibility of pregnancy, ovulation refers to the period of ovulation, the specific time is not certain, after ovulation, the egg waiting for fertilization time is 24-72 hours. So in the 8th day of ovulation, it is possible that the egg is viable, this time sex has sperm into the body, it is possible that the sperm, the egg meets to form a fertilized egg, there is a possibility of pregnancy, you need to be in sex about 15 days to test with pregnancy test or sex about 10 days to determine whether the blood test HCG pregnancy. If you are sure that you are pregnant, you need to delay your period for about 1 week to do an ultrasound to check the pregnancy sac in the uterine cavity.