Final answer:
Certain RNA viruses can impact perinatal development if infections occur during pregnancy.
Step-by-step explanation:
A viral infection during pregnancy can have perinatal impact and cause complications in fetal development. For example, Cytomegalovirus (CMV) infection can result in growth retar-dation, jaundice, deafness, blindness, and mental retar-dation if the virus crosses the placenta during the embryonic state. Herpes simplex virus (HSV) infection during pregnancy can also lead to severe disabilities in the fetus. Additionally, Rubella virus can cause congenital rubella syndrome and developmental defects.