Pregnancy can be detected 14 days after intercourse. If you are pregnant after intercourse, you can detect pregnancy by doing a urine test or blood HCG. The fertilization occurs within 24 hours after ovulation, and the fertilized egg lays in about 5-6 days, that is, if you have intercourse during ovulation, 7 days after intercourse, the secretion of chorionic gonadotropin begins in the blood, and at this time, the blood test can detect a small amount of chorionic gonadotropin, so you can detect pregnancy after waiting for a few days. In some cases, pregnancy can be detected about 12 days after intercourse. Generally there are three means to detect pregnancy, one is to do a test strip, one is to do a blood HCG, and the other is to do an ultrasound directly after menopause to see if there is a gestational sac in the uterine cavity to determine if you are pregnant.