All of the following statements about congenital rubella are true, EXCEPT:

Rubella is ateratogenic virus, can be transmitted from fetus to mother. The risk of congenital manifestations is maximum when a women is infected during the first trimester. After 12 weeks' gestation, the risk of congenital malformation decreases markedly. Features of congenital rubella syndrome include microcephaly and encephalitis, cardiac defects (patent ductus aeriosus, pulmonary aerial stenosis, aerial hypoplasia) cataracts, retinopathy, and microphthalmia, growth restriction, hepatosplenomegaly, thrombocytopenia, and purpura and deafness. Presence of IgM antibody in the serum of infant indicates recent infection as IgM does not cross the placenta from the mother as IgG. In an infant with congenital infection, serum IgM antibodies may be present for up to 1 year after bih. A rubella serum IgG titer persisting beyond the time expected after passive transfer of maternal IgG antibodyis another serologic criterion used to confirm CRS.