Approximately 5 million babies with birth defects are born each year worldwide, 85 per cent of them in developing countries. China is one of the countries with a high incidence of birth defects in the world, with about 800,000 to 1.2 million birth defects born each year. Severe birth defects can lead to the death or permanent disability of newborns and children. Birth defects are a serious public health problem and have gradually become the leading cause of infant and child mortality in developing countries. The direct economic loss caused by neural tube malformations in China exceeds 200 million yuan annually, the cost of treating congenital anomalies exceeds 2 billion yuan, and the cost of treating congenital heart defects is as high as 12 billion yuan. In 2003, new regulations on marriage registration came into effect, abolishing mandatory premarital examinations and making them voluntary. It should be said that this is an improvement. However, the number of infectious diseases and various types of diseases affecting pregnancy found during pregnancy checkups in various places has increased significantly since 2004. Birth defects will lose their first fence! It was reported that 52 pregnant women with syphilis in pregnancy were found by prenatal checkups in Nanjing Maternal and Child Health Hospital during 2 years; among them, 4 cases of gonorrheal ophthalmia were found among newborns ready to be discharged from the hospital, which was very rare in the past. Among all neonatal birth defects, there is a high incidence of neural tube malformations, including spina bifida and anencephaly; harelip, deafness, limb anomalies and congenital stupidity are also common, and hydrocephalus and congenital heart disease are more prevalent. Prevention: Folic acid can be taken three months before pregnancy. “Birth Defects Prevention Day was established to remind people that to reduce the number of defective babies, it is necessary to conduct scientific, standardized, and comprehensive health care and examinations at an early stage. Those who are going to get married and families who are going to have children should, from the perspective of being highly responsible for their own health, the health of others and the health of their children, seriously do a good job in pre-marital counseling, pre-marital checkups, pre-pregnancy counseling, pregnancy checkups, prenatal checkups and prenatal diagnosis in order to minimize the occurrence of defective babies, especially those who are likely to be at high risk of having defective babies and who should be more attentive to this, including those who have a history of hereditary diseases on both sides or in their families; those who have previously given birth to a child with genetic diseases; and those who have had a child with genetic diseases. These include those who have a history of genetic diseases in both parties or in their family line; those who have given birth to children with genetic diseases or congenital malformations; those whose parents have unexplained mental retardation; those who have a history of recurrent miscarriages and stillbirths; those who have a history of exposure to adverse environmental factors during pregnancy; those who have been infertile for many years after marriage; and those pregnant women who are older than 35 years of age. Emphasizing premarital and pre-pregnancy examination and health care can effectively prevent the occurrence of defective children; focusing on pregnancy examination and prenatal diagnosis can create conditions for intrauterine treatment of the fetus or selective abortion, which can reduce birth defects; necessary screening of newborn babies after birth can detect the presence of diseases at an early stage and enable defective children to receive timely treatment. In addition, the first trimester of pregnancy is crucial to the development of the fetus, pregnant women in the first trimester of pregnancy must pay attention to, as far as possible to avoid contact with toxic and radioactive substances; in order to avoid the occurrence of neural tube malformations, if you want to get pregnant women, in the preparation of pregnancy in the first trimester and the early trimester of pregnancy can be supplemented with small doses of folic acid.