The Society of Obstetricians and Gynecologists of Canada are recommending that pregnant women or women planning to conceive should know whether they are immune to chickenpox as the varicella zoster virus poses a high risk both to the pregnant women and to their fetuses.
The recommendations suggest that women who are planning to conceive and who are not immune to the virus should be vaccinated at least 4-weeks before conception. While, women who are already pregnant should not be vaccinated during their pregnancy, as the vaccine is made with live attenuated viruses.
The guidelines do not recommend the termination of a pregnancy if a woman is inadvertently vaccinated against chickenpox while she is pregnant.
The recommendations are being made as the risk of a fatal infection is higher in pregnant women, particularly those infected during the third trimester. Also, women who become infected during pregnancy are at risk of developing a condition call pneumonitis (inflammation of the lungs).
Chickenpox virus can cross the placenta and harm the fetus. Children born to mothers who were infected during the first half of pregnancy can have congenital malformations or deformations, including partial limb reduction or chest wall malformations, as well as brain and central nervous system abnormalities. If the mother is infected late in the pregnancy, or the baby is exposed to the virus 5-days before or during delivery, the baby can develop neonatal varicella, a potentially serious threat.