Definition of assisted reproductive technology: methods for operating sperm, eggs and embryos in vitro to help infertile couples conceive, including artificial insemination, in vitro fertilization embryo transfer (commonly known as IVF technology) and its derivative technologies. There are several types of artificial insemination. First, they are divided into the sperm source and the sperm source for sperm. The sperm usually comes from the sperm bank. The second is divided into intravaginal insemination, cervical insemination, intrauterine insemination (IUI) and intrafallopian insemination according to the insemination site. Intrauterine instruction is currently most commonly used. Because the uterine cavity is a sterile environment, semen must be processed, generally two methods: upstream method and density gradient method. The treated sperm is made into 0.3-0.5 ml sperm suspension and injected into the uterine cavity through the cervix with a sterile catheter. The technical scientific name of IVF is in vitro fertilization embryo transfer technology. Main process: Remove the egg from the female body and fertilize the sperm in vitro, and after culturing for another 3-5 days, transfer the formed embryo back to the uterus. Main steps: Drug ovulation (drugs stimulate the ovaries to form multiple follicles. The drug used for test tubes to promote ovulation has a special name called superovulation, referred to as superovulation), under the ultrasound monitoring, vaginal puncture of the ovary, ovulation, masturbation and semen Treatment, in vitro fertilization (conventional fertilization and single sperm injection fertilization), in vitro culture for 3-5 days, selection of embryos for transplantation, corpus luteum support (commonly known as fetal protection). General conventional in vitro fertilization embryo transfer technology is a standard technology, and the technologies derived and developed from it include: intracytoplasmic sperm injection technology (ICSI), pre-implantation genetic diagnosis and screening technology (PGD / PGS), sperm, Egg and embryo cryopreservation technology (vitrification cryopreservation technology), blastocyst culture (BC) and egg in vitro maturation technology (IVM). The most serious complication of assisted reproductive technology is ovarian hyperstimulation syndrome (OHSS). Mild and moderate can be observed, while severe cases must be hospitalized symptomatically, severe cases can be life-threatening. The main manifestations of severe OHSS: severe gastrointestinal symptoms, markedly enlarged ovaries, ascites, pleural effusion and even pericardial effusion, blood concentration, thrombosis, electrolyte disturbance, and impaired liver and kidney function. Divided into early-onset and late-onset, the former is related to the night needle’s hcg (amount), the latter is related to the hcg secreted by the embryo after pregnancy. The main pathological change is the increase in the permeability of blood vessels throughout the body, and the water in the blood enters the cavity of the human body and the blood is concentrated. OHSS is a self-limiting disease, the treatment is mainly symptomatic, and it will be cured after the most difficult period. Really serious can only terminate pregnancy as soon as possible. With the development of technology, more and more ethics and even legal issues are involved in assisted reproductive technology, which requires high attention.