Varicella zoster virus (VZV) is a common illness that causes varicella (chickenpox) and shingles. It is prevalent mostly during childhood but there are additional co-morbidities from this disease for a woman and her fetus, if she contracts it during pregnancy. Many developed countries vaccinate children who have not acquired immunity to prevent their developing complicated varicella as adults. Countries that have implemented widespread vaccination have fewer hospital admissions for such complications.

The UK does not have a national VZV vaccination programme and there is no strategy for reporting and documenting the incidence of the illness, so it is difficult to determine the potential prevalence of gestational VZV and its associated outcomes. The aim of this article is to provide an understanding of the aetiology of VZV and the potential health risks to unimmune women who may contact it during pregnancy, to advise them about their healthcare choices.