The steps of IVF vary somewhat depending on the patient’s specific situation. It can be as simple as in vitro fertilization and embryo transfer, or it may be in vitro fertilization plus other assisted reproductive techniques such as microfertilization, assisted hatching, surgical methods of sperm retrieval, in vitro maturation of eggs, egg/sperm/embryo freezing, and preimplantation diagnosis. The basic steps of IVF are: production of several eggs by the woman, removal of the eggs from the ovaries and sperm from the man, fertilization of the sperm and eggs in the IVF laboratory, in vitro culture of the fertilized eggs in order to select good embryos for transfer, transfer of the embryos to the patient’s uterus, pregnancy support after the embryo transfer, pregnancy tests after the embryo transfer, post-pregnancy fetal days and determination of the embryo implantation site. The procedure is used to determine the location of the embryo. (1) Pre-insemination processing and ovulation monitoring: In order to collect pre-ovulatory mature or near-mature oocytes from the ovaries at the right time, it is extremely important to accurately monitor the process of follicular maturation prior to ovulation. Often only one oocyte can be retrieved using the natural menstrual cycle for egg collection. To increase the chances of success and to increase the number of developing follicles to obtain multiple eggs, stimulated cycles (also known as superovulation) are now commonly used to obtain more than 3 oocytes at a time. ① Pre-ovulatory monitoring during natural menstrual cycle: The first successful IVF case in the world was performed using natural cycle monitoring for ovulation. The day of egg retrieval is determined by basal body temperature measurement, endocrine measurements (blood estradiol values, luteinizing hormone values in urine) and ultrasound monitoring, together with clinical observations (changes in cervical mucus, etc.). ② Ultrasound monitoring: should be closely coordinated with endocrine measurements. (③) Ovulation promotion: Currently, there are four main regimens for ovulation promotion: clomiphene-human postmenopausal gonadotropin (HMG)-chorionic gonadotropin (HCG); HMG-HCG; follicle stimulating hormone (FSH)-HCG; gonadotropin Clomiphene-HMG-HCG regimen is routinely used. (2) Egg collection: The eggs are collected at a determined time. (2) Egg collection: The eggs are collected at a determined time. (2) Trans-laparoscopic egg retrieval. (3) Ultrasound-guided transabdominal wall, urinary bladder or vaginal puncture for egg retrieval. At present, trans-laparoscopic or ultrasound-guided transvaginal egg retrieval is mostly used, the latter being particularly convenient. (3) Oocyte culture: Immediately after aspiration of follicular fluid, the eggs are searched for. After the oocytes are removed, they are placed in a culture dish with artificial culture fluid and a certain amount of follicular fluid, which helps the growth and development of the oocytes. The incubation time depends on the maturity of the follicles removed, and the mature ones are usually incubated for 2-6 hours. (4) In vitro fertilization: The semen is collected and washed to enable the semen to be used in vitro, then placed in a culture medium with oocytes and incubated for 15~24 hours. When the microscopic observation shows that the fertilized egg has divided to 4~8 cells, it can be considered for embryo transfer. (5) Embryo transfer: The vagina and cervix are cleaned with saline and then scrubbed with culture solution, and a metal or plastic catheter is placed into the cervical canal. Another assistant will aspirate embryo cells from the culture fluid under the microscope with a 1.3mm PTFE tube plus 0.03~0.05ml of culture fluid or 0.03~0.05ml of subject serum, insert this tube into the cervical canal catheter to 0.5cm from the uterine fundus, and send the embryo into the uterine cavity. After embryo transfer, the embryos need to be bedridden for 24 hours, restrict activity for 3-4 days and receive progesterone therapy. Beta-GCG measurement is done 2 weeks after transfer and progesterone is discontinued if there is no pregnancy. Pregnancies with successful transfer are monitored as high-risk pregnancies.