It is quite common for siblings to suffer from precocious heart disease at the same time, and for parents and children to suffer from precocious heart disease at the same time, and the nature of the disease is very similar. If the first child born to a mother with precocious heart disease, the likelihood of the second child having the disease is about 2%; if two consecutive children are born with precocious heart disease, the risk of having another child with precocious heart disease may increase to 10%. If the mother has prediabetes, the risk of prediabetes in the second generation is 10%. Pregnant women with untreated and uncontrolled diabetes mellitus have a 2% risk of congenital heart disease in the fetus, and the risk decreases if the disease is controlled and stabilized early in pregnancy. Exposure to teratogenic drugs such as lithium, phenytoin sodium or steroids in early pregnancy can lead to a 2% risk of fetal congenital heart disease. Excessive exposure to radioactive substances such as X-rays and isotopes in early pregnancy. Viral infections. Viral infections in the first trimester of pregnancy, especially in the third to eighth weeks of pregnancy, can predispose the fetus to cardiovascular malformations. The rubella virus is the main culprit of fetal precocious heart disease. In addition, influenza, mumps, coxsackie virus, herpes virus, etc. are also often the “perpetrators” of pediatric precocious heart disease. Inbreeding. Consanguineous marriage is a high risk factor for fetal malformation and precocious heart disease. Bad habits. Pregnant women who are addicted to “smoke” or husband smoking, wife “passive smoking” can cause fetal malformations or pediatric precocious heart disease. The incidence of pre-cardiac disease in infants, babies born to smoking mothers is two times that of non-smoking mothers. Couples who conceive “after drinking” can cause chromosomal abnormalities in the fetus and give birth to babies with alcoholism, most of which have cardiovascular abnormalities.