Foetal infection occurs in 10-15% of cases or varicella in pregnant women. The most common clinical manifestation, if any occurs, is shingles in the first year of life.
However, 2-3% of infants of mothers with chicken pox in first half of pregnancy develop foetal varicella syndrome with potentially severe defects:
- skin scarring in dermatomal distribution
- ipsilateral limb hypoplasia
- visceral
- neurological
- eye lesions
- ? cardiac abnormalities
maternal infection within a few days before and after delivery can result in potentially severe varicella in the infant → give infant ZIG (zoster immune globulin) ASAP after birth.
More than 90% of women of child-bearing age are immune to chicken pox (vaccination), but a history of infection also provides reliable evidence of immunity.
Consider if contact (exposure to V-Z) occurred
- give varicella IgG (ASAP) if negative serology
- ZIG within 48 hours (max. 72 hours) of contact
- reduces illness severity even if does not prevent infection
- ineffective after onset rash
High-risk women (e.g. CAL, smokers, immunocompromised latter half of pregnancy, within incubation window period, soon after onset rash, those not had ZIG) with disease progression require admission for intravenous acyclovir which, although not routinely recommended in pregnancy, seems to have no adverse foetal effects.
