SBA — Single Best Answer · Review
Question 731
Obstetric infection → Viral
Classification
Question
SSBAQuestion Header
Evidence of maternal varicella immunity
Question Stem
A healthy pregnant woman has significant contact with chickenpox. She reports receiving two documented doses of varicella vaccine before pregnancy. What is the most appropriate interpretation?
Options
A
She can reasonably be assumed to be immune to varicella
B
She must receive VZIG regardless of vaccination history
C
She should receive oral aciclovir immediately on the day of exposure
D
Two vaccine doses provide no useful evidence of immunity in pregnancy
E
She requires varicella vaccination during pregnancy
Explanation
In an otherwise healthy pregnant woman, a definite previous history of chickenpox or shingles, or receipt of two doses of varicella vaccine, is considered reasonable evidence of immunity. If immunity is uncertain or the history is doubtful, VZV IgG should be measured. Immunosuppression is an important exception because previous infection or vaccination may not provide sufficient evidence of immunity in that setting.
Option Validity
B) VZIG is not automatically required when there is reasonable evidence of immunity.
C) first-line antiviral PEP is for a susceptible woman after significant exposure and is not started immediately on the day of exposure.
D) two documented vaccine doses are reasonable evidence of immunity in an otherwise healthy woman.
E) varicella vaccine is not administered during pregnancy.
Further Reading
RCOG Green-top Guideline No. 13, Chickenpox in Pregnancy, section 4.3.