Generally, you can test if you are pregnant on 22 days after intercourse. If the egg and sperm can combine normally after intercourse to form a fertilized egg, it usually enters the endometrium to grow and develop 6-8 days after fertilization, a process known as implantation. The fertilized egg secretes chorionic gonadotropin, or HCG, and participates in the maternal circulation. A blood test will reveal an elevated level of HCG in the blood, and pregnancy will be detected. In addition to the blood test, a urine pregnancy test using early pregnancy test paper at this time can also generally find a positive reaction and can be used to initially determine pregnancy. If pregnancy is detected through urine and blood tests, it is only clear that the pregnancy is a state of pregnancy, but it is still difficult to determine whether it is an intrauterine pregnancy, and further ultrasound tests are needed to rule out ectopic pregnancy. It should be noted that some women have irregular or long menstrual cycles, and ovulation may be delayed or irregular, so it may be difficult to determine whether pregnancy is present after 22 days of intercourse.