Fetal malformation is a kind of birth defect, which refers to various structural abnormalities occurring in the fetus in utero, and the causes of occurrence mainly include genetics, environment, food, drugs, viral infections, etc. 1, maternal factors: such as pregnant women suffering from diabetes, vascular diseases, bronchial asthma, chronic nephritis, maternal chromosomal defects, viral hepatitis, etc.; or the lack of certain vitamins or trace elements in the mother’s body may cause fetal malformations. 2.Parental exposure to harmful environment: such as smoking, drinking, noise, high temperature, low pressure, indoor and outdoor air pollution, long-term exposure to radiation, pesticides, exposure to chemicals, organic compounds such as gasoline, metals (lead, aluminum, mercury, arsenic, etc.). 3, the use of drugs prohibited during pregnancy: such as sedatives, hormones, sulfonamides, antimicrobials, anticonvulsants, antitumor drugs, antimalarial drugs, antithyroid drugs, anticoagulants, antipyretic and analgesic drugs, etc. 4, intrauterine infection: such as infection with rubella virus, cytomegalovirus, herpes simplex virus, varicella-zoster, syphilis spirochetes, toxoplasma, malaria parasites, etc. during pregnancy. As mentioned above, there are many causes of fetal malformation, which may be one factor or a combination of factors. In order to prevent fetal malformation, pregnant women should be well protected during pregnancy, have regular checkups and be more aware of eugenics.