Pregnancy can be detected by serum chorionic gonadotropin 3-4 days after fertilization of the egg. Pregnancy can usually be detected in about 14 days if detected by morning urine using an early pregnancy test. It takes about 1 week for the fertilized egg to settle. On day 6 after fertilization, the body’s syncytial trophoblast cells begin to secrete trace amounts of chorionic gonadotropin, which can be detected in the maternal serum 10 days after conception. Therefore, pregnancy can be detected by chorionic gonadotropin 3-4 days after fertilization of the egg. Pregnancy is indicated when a chorionic gonadotropin value of more than 5 U/L is detected. If the morning urine test is used to detect pregnancy, it usually takes about 14 days for the fertilized egg to become positive. In addition, pregnant women should be aware that a chorionic gonadotropin test cannot determine intrauterine or ectopic pregnancy and that further ultrasound examinations at 6-8 weeks of pregnancy are required for final confirmation.