The natural cycle process of blastocyst transfer is in the following order: adjusting endometrial thickness, monitoring ovulation, and performing the transfer. 1. Adjusting endometrial thickness: before carrying out blastocyst transfer, it is necessary to adjust the endometrial thickness first. 2. Monitoring ovulation: It is recommended to start ultrasound to monitor ovulation around the 10th day of menstruation. When the follicle grows to 1.8~2.0cm and is normally discharged, progesterone will be given to support it. 3. Perform transfer: transfer cleavage stage embryo on the 3rd day or transfer blastocyst on the 5th day after ovulation. Blastocyst transfer natural cycle is mainly for women with normal ovulation and regular menstruation, but for the specific process, it is recommended to go to the hospital, and after the doctor’s interview, according to the patient’s specific situation, a reasonable transfer program will be formulated.