During pregnancy, if a pregnant woman is infected with rubella virus, it poses a significant risk to the fetus, primarily causing congenital developmental abnormalities. For example, there may be cardiac malformations, congenital heart disease, cataracts, and deafness. Some may experience delayed brain damage during infancy after the baby is born, as well as diabetes or other central nervous system disorders. When rubella virus infection occurs, it is generally advised to consider terminating the pregnancy. The risk of fetal infection and congenital malformations is highest in early pregnancy, potentially exceeding 80%.