Risk to Baby if Pregnant Woman Contracts Shingles
If a pregnant woman develops shingles (herpes zoster), there is essentially no risk to the fetus—maternal shingles does not cause congenital varicella syndrome, fetal transmission is extremely rare, and no increased fetal mortality has been documented. 1, 2, 3
Key Distinction: Shingles vs. Chickenpox
The critical point is that shingles (herpes zoster) is fundamentally different from chickenpox (primary varicella infection) in pregnancy:
- Shingles represents reactivation of latent varicella-zoster virus (VZV) from prior infection, not a new primary infection 2, 3
- In a large prospective study of 1,373 pregnancies, zero cases of congenital varicella syndrome occurred among 366 mothers who had herpes zoster during pregnancy 1
- Passage of VZV to the fetus during maternal shingles "rarely occurs" 2
Fetal and Neonatal Outcomes
No Congenital Syndrome Risk
- Maternal shingles does not result in congenital varicella syndrome (the pattern of limb hypoplasia, scarring, microcephaly, and eye abnormalities seen with primary maternal varicella) 1, 2
- No increased fetal mortality has been documented 2
Minimal Neonatal Impact
- Approximately 20% of newborns whose mothers had shingles during pregnancy may develop neonatal or infantile herpes zoster, but this occurs without complications 3
- These cases represent benign reactivation in the infant, not serious disease 3
Maternal Considerations
While the fetus is safe, maternal morbidity from shingles and its complications is the primary concern:
- Pregnant women with uncomplicated shingles should receive oral acyclovir to reduce symptom severity and duration 2, 3
- Treatment is recommended to accelerate healing and reduce pain, though it does not eliminate transmission risk 4, 3
- Major complications include subacute and post-herpetic neuralgia, zoster ophthalmicus, disseminated zoster, and secondary bacterial infections 2
Common Pitfall to Avoid
Do not confuse shingles with chickenpox exposure or infection. The management and fetal risks are completely different:
- Chickenpox (primary varicella) in pregnancy carries significant fetal risks including congenital varicella syndrome (0.4-2% risk depending on gestational age) and severe neonatal disease 1
- Shingles (reactivation) in pregnancy carries essentially no fetal risk 1, 2
If a pregnant woman is exposed to someone with shingles and has no immunity to varicella, she requires the same post-exposure prophylaxis as chickenpox exposure (VZIG within 96 hours), but this is about preventing primary maternal infection, not treating shingles itself 1, 4