Generally the probability of chromosomal abnormalities causing fetal malformations is still relatively high, and the details vary from person to person. Chromosomal abnormality refers to changes in the number and structure of chromosomes, and is a common congenital genetic disease. Its onset may be related to genetic, chemical, physical and other factors, mainly manifested in multiple malformations, mental retardation, growth retardation and other symptoms. In general, the probability of chromosomal abnormality causing fetal malformation is still quite high, due to the different manifestations of chromosomal abnormality in different populations, the specific situation varies from person to person. Fetal chromosomal abnormalities can cause a variety of malformations, depending on the type of chromosomal abnormality. It is recommended that pregnant women take folic acid tablets before pregnancy, stay away from polluted environments and pets, maintain a good mindset and lifestyle habits, and do all the examinations during pregnancy.