1.Visit the clinic, determine the IVF treatment, sign the informed consent form and perform the routine preoperative examination. 2.Prepare original and copy of documents (ID card, marriage certificate, birth certificate). 3.Follow the doctor’s instruction to use medication for ovulation and follicle monitoring. 4.Mature follicles are injected with HCG on the same night (8:00-8:30 pm), and the laboratory chart is established on the day of HCG injection and the relevant informed consent is signed. 5. 36 hours after HCG injection, egg retrieval is performed by ultrasound-mediated puncture and aspiration of the follicular fluid, which takes about 5-10 minutes. 6.On the day of egg retrieval, the male partner will take the semen, determine the specific treatment plan and sign the relevant informed consent form. 7. 2-6 hours after egg retrieval, fertilization will be observed on the next day and embryo transfer will be routinely performed on the third day. 8. From the day of transfer, morning urine will be measured for 14 days to check the fertilization status and inform our center by phone.