Pregnancy can be detected by serum test at 7 days or more after transfer and urine test takes 14 days to detect pregnancy. Embryos for IVF transfer are usually 3-day embryos or blastocysts. Pregnancy can be initially observed by testing a woman’s blood for human chorionic gonadotropin levels in her blood 7 days after the transfer, while a urine test takes more than 14 days to detect it. Early increase in blood level of human chorionic gonadotropin does not necessarily indicate intrauterine pregnancy, but there may be biochemical pregnancy, ectopic pregnancy, embryo abortion, etc. Therefore, it is necessary to monitor the level of human chorionic gonadotropin dynamically, and when it reaches a certain level, obstetric ultrasound will be conducted to confirm the development of the transferred embryo. If you have any other questions, it is recommended to consult a professional doctor for guidance.