Q. Is chicken pox dangerous during pregnancy? Should I get the vaccination before getting pregnant? How long do I have to wait before conceiving after vaccination?
A. Chickenpox is a very infectious illness caused by a virus called herpes zoster.
It usually causes an itchy red rash with blisters but can occasionally affect the lungs (pneumonia), the liver (hepatitis) and the brain (encephalitis). Very rarely, pregnant women may die from these complications.
For the unborn baby, the risk of getting chickenpox depends on the stage of the pregnancy when the mother gets infected. The highest risk is during the last 4 weeks of pregnancy.
If the mother has chickenpox:
· before 28 weeks of pregnancy, the baby is unlikely to be affected. However, there is a small chance (less than 1 in 100) that damage could occur to the eyes, legs, arms, brain, bladder or bowel. There is no increased risk of miscarriage.
· between 28 and 36 weeks of pregnancy, the virus will stay in the baby’s body but will remain asymptomatic. The virus may become active again, causing shingles in the first few years of life.
· after 36 weeks of pregnancy, the baby is at greatest risk of getting chickenpox. Chickenpox rash may appear after birth and the baby may have severe complications involving lungs, liver or brain.
It is advisable that you get your blood checked first to find out whether you have the immunity against chickenpox. If you do not have the immunity, you should get vaccinated before getting pregnant.
The vaccine contains a weakened form of the chickenpox virus and works by causing the body to produce antibodies (resistance) to protect against the disease.
The vaccine should not be given during pregnancy and you should avoid getting pregnant for 3 months after the injection, based on guidelines by the Royal College of Obstetricians and Gynaecologists, U.K.
It is given in two doses, one to two months apart.
The vaccine can have side effects but they are usually mild. They include:
- Redness, swelling, or soreness at the injection site.
- Mild fever
- Mild chickenpox-like rash, usually within a month of vaccination
- Allergic reaction, usually mild.