Pregnancy can be detected after the formation of a fertilized egg. It takes about a week for a fertilized egg to form after intercourse, and the body will begin to secrete chorionic gonadotropin after the formation of the fertilized egg, and you can determine if you are pregnant by taking a blood test for chorionic gonadotropin around 10 years into your pregnancy. If you test by early pregnancy test paper, this test will take slightly longer, usually about half a month after the formation of fertilized eggs can be measured whether the pregnancy. It is important to use morning urine, the first time you wake up in the morning to urinate, as this will be more accurate. If you have had sex to detect whether you are pregnant or not, it is recommended that you take a blood test for chorionic gonadotropin, which is more accurate and takes less time.