HCG refers to human chorionic gonadotropin, and women with elevated HCG after in vitro transfer of fresh embryos may experience early pregnancy reactions. HCG is secreted by placental syncytial trophoblast cells, if the in vitro fertilization of fresh embryos is successful, there are trophoblast cells in the woman’s body, which are able to produce HCG, and with the increasing level of HCG, the woman will experience early pregnancy reactions such as nausea, dizziness, fatigue, lethargy, lack of appetite, liking acidic food, aversion to greasy food and vomiting in the morning and some of them will also experience changes in their moods. If women experience abdominal pain, vaginal bleeding and other symptoms after IVF fresh embryo transplantation, it is recommended to consult a doctor in time, under the guidance of the doctor, complete the relevant examinations, clarify the cause of the disease and treat the symptoms.