Conventional in vitro fertilization embryo transfer (IVF-ET): A technique to remove gametes from the human body and fertilize them under in vitro conditions to form embryos, then transfer them to the uterine cavity for implantation to establish pregnancy, also known as IVF. Indications: 1. Gamete transport disorders caused by various factors in the female partner: such as bilateral tubal obstruction, tubal agenesis, severe pelvic adhesions or history of tubal surgery, etc. Loss of tubal function. 2. Ovulation disorder: refractory ovulation disorder after repeated conventional treatment, such as repeated induction of ovulation or COS, or those who have not obtained pregnancy even after treatment with intrauterine insemination technique. 3.Endometriosis: endometriosis causes infertility and pregnancy is not obtained after conventional drug or surgical treatment. 4.Low, weak and teratozoospermia of the male partner: male infertility with low, weak and teratozoospermia of the male partner or compound factors, and pregnancy has not been obtained after treatment with intrauterine insemination technique, or the severity of the male factor is not suitable for the implementation of intrauterine insemination. 5. Immune infertility and unexplained infertility: those who have not obtained pregnancy after repeated intrauterine insemination or other conventional treatments. Steps of routine IVF-ET treatment: Infertile couples should complete the preoperative preparation before IVF-ET, and must complete systematic infertility examination and routine physical examination to exclude medical and surgical diseases and tumors that cannot tolerate ovulation and pregnancy, and confirm that the patient has appropriate indications and no contraindications before entering the treatment cycle. 1. Pre-treatment examination: The following examinations are required before the IVF procedure for women: general physical examination, electrocardiogram, chest X-ray, blood routine, blood group, urine routine, liver function, kidney function, hepatitis series, ovarian function (FSH, LH, E2, PRL, T), routine gynecological examination, chlamydia and mycoplasma of cervical secretions, syphilis, HIV, eugenics series (HSV-I-IgM, HSV-II-IgM), HSV-II-IgM, rubella virus antibody, toxoplasma antibody, cytomegalovirus antibody). The male partner needs to do the following tests: semen routine ≥2 times, liver function, kidney function, hepatitis series, syphilis, HIV. 2. Before starting the treatment, explain in detail to the couple the whole process of treatment, possible complications and their treatment methods, including possible treatment failure caused by the female partner’s non-response to ovulation promotion, egg retrieval failure and unfertilization. 3. Controlled ovarian hyperstimulation and follicular development monitoring (COH): (1) GnRH agonist hyporegulation regimens (including long, short and extra-long regimens starting from the luteal phase); (2) non-hyperregulated hyporegulation regimens; (3) GnRH antagonist hyporegulation regimens (3) superovulation protocols using GnRH antagonists. A monitoring protocol including at least ultrasound and blood hormone level measurement is developed and carefully implemented according to the treatment protocol. When there are follicles ≥14mm in both ovaries after ultrasound monitoring of superovulation medication, daily monitoring of urinary LH peak is required; when there are more than 3 follicles with mean diameter ≥16mm or 2 follicles ≥17mm or 1 follicle ≥18mm, while referring to blood sex hormone levels, consider using HCG at a routine dose of 10000iu and retrieve eggs 36-38 hours after injection. 4, Egg retrieval: Ultrasound guided transvaginal puncture for egg retrieval, aspiration of follicular fluid and obtaining oocytes from it. 5.In vitro fertilization: 2-6 hours after egg retrieval, the oocytes are fertilized in vitro with sperm treated by gradient centrifugation or upstream method at a density of 50,000-100,000 sperm/egg. 6.Embryo transfer: After 48-72 hours of culture of fertilized eggs (blastocysts can be obtained after 5 days of in vitro culture), 1-3 embryos of good quality are implanted into the uterine cavity and bed rest is given for 1-6 hours after the procedure. 7. Luteal support: Luteal support is usually needed after IVF-ET, usually with HCG or progesterone. 8.Follow up: urine HCG test or blood βHCG measurement two weeks after surgery to determine whether pregnancy, and ultrasound examination of gestational sac, germ bud and heart tube pulsation 2-3 weeks after a positive pregnancy to determine clinical pregnancy.