The effects of Cytomegalic virus (CMV) infection during pregnancy on the developing human fetus

In most instances Cytomegalic virus causes a sub-clinical infection, rendering the pregnant mother unaware of being infected. However, primary CMV is the most common infection during pregnancy that may have long-term neuro-developmental sequelae in 10%-20% of children born to these mothers. The clinical findings in these children include intrauterine growth restriction (IUGR), microcephaly, hearing and visual impairment, developmental delay, mental retardation and various neurological deficits. Serological diagnosis of primary CMV in the mother is difficult because IgM antibodies persist for long periods of time and both IgG and IgM antibodies may rise during secondary infection that is generally less dangerous to the human embryo in comparison to primary infection. A more reliable diagnostic procedure is to assess fetal infection by polymerase chain reaction (PCR) and CMV culture performed in amniotic fluid at least 6 weeks following presumed maternal infection and past the 21st week of pregnancy. Due to the difficulties in serological diagnosis and the common lack of typical clinical findings, there seems to be no reason to perform routine serological studies for CMV in pregnant mothers or in women prior to planning pregnancy. The best preventive measure is appropriate immunization against CMV, but no effective immunization seems to exist as of today.