Early pregnancy can be detected seven to ten days after ovulation and requires a blood test for human chorionic gonadotropin in the blood. This hormone is secreted into the bloodstream, and a blood test can confirm pregnancy. It takes one to two days for the sperm to unite with the egg after intercourse, and six to seven days for the fertilized egg to take hold, so it takes seven to ten days after intercourse to go to the hospital to have a blood test to determine if you are pregnant. If you use the early pregnancy test to check the human chorionic gonadotropin in the urine later, it is checked after a week of delayed menstruation. So the earliest you can check for pregnancy is one week after your period, and the latest it takes is twenty days. If you have intercourse during ovulation and do not use contraception, and want to know if you are pregnant as soon as possible, it is best to go to the hospital to have a blood test to be sure, and after its pregnancy is confirmed, pay attention to rest to avoid miscarriage.