Last reviewed 01/2018
The foetus does not produce specific IgM until 23 weeks gestation and no methods able to detect these in cord blood are currently in use - PCR is being evaluated.
Congenitally infected babies are identified by detecting rubella virus specific IgM in the infant's blood:
- less than 3 months, 100% IgM positive
- 3 to 6 months, 90% IgM positive
- 6 to 12 months, 50% Igm positive
Thrombocytopaenia is common.