Pregnancy test is through the immune response to detect human chorionic gonadotropin in human urine, generally 7-10 days after intercourse may be detected, and menstruation delayed 3-5 days to detect more accurate. After intercourse, the sperm and the egg combine to form a fertilized egg, the fertilized egg in the uterus bed development, the body can secrete human chorionic gonadotropin (HCG), but at this time the amount of HCG is relatively small, generally 7-10 days after intercourse pregnancy test stick may be detected. The test results will be more accurate after another 1-2 weeks, i.e. about 15-20 days after intercourse, the pregnancy test stick can detect it more accurately. For women with regular menstrual cycles, pregnancy can be detected by using a pregnancy test 7-15 days after intercourse; for women with irregular menstrual cycles, especially those who often have delayed periods, it can usually be detected 6 weeks after menopause. If the result of pregnancy test cannot be determined, it is recommended that the patient go to the hospital to take a blood test for HCG, and the result of the blood test will prevail.