Neural tube defects mainly include anencephaly, spina bifida and brain herniation, accounting for 45%, 45%-50% and 5%, respectively, and the incidence varies by region and country. In the United States, the incidence is 0.1%-0.2%, in Japan, 0.12%, and in the northern part of China, the incidence is higher at 0.1%-0.2%. The ratio of males to females is 1:1.3. neural tube defects are thought to be a disease caused by multifactorial interactions, including genetic and non-environmental factors. more than 90% of cases occur sporadically. Normally, the neural plate forms on day 18 of gestation and the neural tube closes around the fourth week of gestation. In early embryonic life, the central portion of the ectoderm thickens and subsequently folds into the neural tube by forming a groove. Failure of the neural tube to close due to genetic or external factors influencing the formation of the neural tube results in open neural tube malformation. It is generally believed that anencephaly occurs within 3 weeks of early embryonic development. Clinical features: 1. Anencephaly: It is the most serious type of neural tube defect. It is caused by non-closure of the top of the neural tube. Almost all anencephalic malformations die within hours or days after birth. 2, spina bifida: spina bifida is the most common type of neural tube defect, spinal herniation and spinal herniation are also attributed to it, with a perinatal mortality rate of 5%-10%. There is usually urinary and fecal incontinence, hydrocephalus and paraplegia. It is associated with moderate to severe mental retardation. 3. Brain herniation: less common. It is caused by a defect in the neural tube against the rhombencephalon. The brain tissue protrudes out of the skull and is encapsulated by a closed sac-like tissue. Severe neurological symptoms and mental retardation mostly occur. Treatment: mainly includes: 1. surgical repair, for minor spina bifida and minor brain herniation can be surgically repaired, usually intrauterine repair is performed at 20-25 weeks. 2. Treatment of hydrocephalus, which can be treated with dehydrating drugs. 3.Control of infection: pay special attention to the treatment and control of infection of the neurocentral system and genitourinary system. 4.Growth and development intervention: pay attention to the treatment of growth and development of the viable patients. 5.Psychological counseling. Prevention: 1, prenatal screening and diagnosis. 2.Ultrasonic diagnosis: High-resolution ultrasonography can detect most of the neural tube defects. 3.Pre-conception folic acid administration has been shown to be an effective measure to reduce the incidence of NTD; attention should be paid to simultaneous vitamin B12 supplementation during folic acid administration to avoid vitamin B12 deficiency anemia.