If conception occurs during intercourse, the blood chorionic gonadotropin can be checked at the earliest around the 10th day after intercourse, and the value is higher than normal. If the pregnancy is 4 days short of menstruation, the blood chorionic gonadotropin can be found to be higher than normal and the pregnancy can be confirmed. Because the time of conception is short, the chorionic gonadotropin value is very low. It is recommended to monitor the blood chorionic gonadotropin dynamically to know the rise of the blood chorionic gonadotropin and to have an ultrasound examination to clarify the location of the gestational sac and its development. If there are no uncomfortable symptoms such as back pain, abdominal pain or vaginal bleeding, it is recommended to go to the hospital for ultrasound examination around 6-7 weeks of pregnancy and review it if necessary. If there is any discomfort, go to the hospital in time.