Rubella and pregnancy

Microbiology

Rubella, also known as German measles, is a viral infection caused by the togavirus. Following the introduction of the MMR vaccine it is now rare. If contracted during pregnancy there is a risk of congenital rubella syndrome. Remember that the incubation period is 14-21 days and individuals are infectious from 7 days before symptoms appear to 4 days after the onset of the rash.

Risk

in first 8-10 weeks risk of damage to fetus is as high as 90%
damage is rare after 16 weeks

Features of congenital rubella syndrome

sensorineural deafness
congenital cataracts
congenital heart disease (e.g. patent ductus arteriosus)
growth retardation
hepatosplenomegaly
purpuric skin lesions
'salt and pepper' chorioretinitis
microphthalmia
cerebral palsy

Diagnosis

IgM antibodies are raised in women recently exposed to the virus

Management

women normally have their immunity checked before becoming pregnant
rubella immunity is routinely checked at the booking visit. If the no immunity is demonstrated pregnant women need to keep away from people who might have rubella
non-immune mothers should be offered the MMR vaccination in the post-natal period