INFECTIONS IN PREGNANCY

Question 1

What is the virus responsible for fetal varicella syndrome?

Answer 1

Varicella zoster virus (chickenpox)

Question 2

What are the features of fetal varicella syndrome?

Answer 2

Skin scarring

Eye defects (microphthalmia)

Limb hypoplasia

Microcephaly

Learning disabilities

Question 3

At what point in the pregnancy is the fetus at risk of developing fetal varicella syndrome?

Answer 3

1% risk before 20 weeks

Very rare after this

Does not occur after 28 weeks

Question 4

Apart from fetal varicella syndrome, what are the other risks (to the fetus) of the mother contracting chickenpox whilst pregnant?

Answer 4

Severe neonatal chickenpox

Shingles in infancy

Question 5

What is the risk of chickenpox to the pregnant mother?

Answer 5

There is a 5 fold increase in the risk of pneumonitis if pregnant with chickenpox vs non-pregnant women

Question 6

How do we manage a mother who is worried about her exposure to chickenpox?

Answer 6

If there is any doubt about the mother previously having chickenpox maternal blood should be urgently checked for varicella antibodies

If the pregnant women is not immune to varicella she should be given varicella zoster immunoglobulin (VZIG) as soon as possible. RCOG and Greenbook guidelines suggest VZIG is effective up to 10 days post exposure

Consensus guidelines suggest oral aciclovir should be given if pregnant women with chickenpox present within 24 hours of onset of the rash