Results are usually given as positive or negative, indicating the presence or absence of IgG and IgM antibodies for each of the infectious agents tested for with the panel. A "normal" result is negative (undetectable) IgM antibody in the blood of the mother or newborn.
Presence of IgM antibodies indicates either a current or recent infection. A positive IgM result in a newborn indicates high likelihood of infection with that organism. IgM antibodies produced in the mother cannot cross the placenta, so presence of this type of antibody strongly suggests an active infection in the infant. Presence of IgG and absence of IgM antibody in an infant may reflect passive transfer of maternal antibody to the baby and does not indicate active infection in that infant. 

Likewise, the presence of IgM antibody in a pregnant woman suggests a new infection with the virus or parasite. Further testing must be done to confirm these results since IgM antibody may be present for other reasons. IgG antibody in the pregnant woman may be a sign of past infection with one of these infectious agents. By testing a second blood sample drawn two weeks later, the level of antibody can be compared. If the second blood draw shows an increase in IgG antibody, it may indicate a recent infection with the infectious agent.

By NeVeZ with