The blood level of human chorionic gonadotropin on the 14th day of blastocyst transfer is usually around 100-500 IU/L, which is normal and proves that the woman has a high chance of pregnancy. If the development of blastocyst is slow or late, the range of blood value may be slightly lower, as long as it exceeds the normal range, it indicates that the woman may be pregnant, so she can observe temporarily, pay attention to proper rest, avoid smoking, alcohol, bacteria, viruses and other unfavorable stimuli, and retest the level of human chorionic gonadotropin after 1 week. The success rate of IVF blastocyst transfer is generally around 30%, which is related to the quality of fertilized egg, endometrial environment and the nutritional status of the woman.