How long it takes to detect pregnancy after intercourse varies depending on the test method and cannot be generalized. After intercourse, the sperm and egg unite to form a fertilized egg and HCG is produced in the blood on the 6th-7th day after the formation of the fertilized egg, therefore, the blood HCG test can be performed about 8 days after intercourse and it is recommended that the test be performed in the morning and the results are more accurate on an empty stomach. If a urine HCG test is performed, it takes 12 days to reach the urine because the fertilized egg secretes HCG, which enters the maternal blood circulation. Therefore, it may take about 12 days for the urine HCG test to detect early pregnancy. In addition, detection of human chorionic gonadotropin alone cannot determine if the pregnancy is intrauterine. It is recommended to observe the presence of a round or oval gestational sac in the uterine cavity by vaginal ultrasound around 40 days after menopause to confirm the diagnosis of intrauterine pregnancy. Since the accuracy of HCG test through urine is lower than that of blood HCG, there are certain false positives and false negatives. It is recommended that women who are not sure if they are pregnant should go to the gynecological department of a hospital for examination.