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Chickenpox and Pregnancy

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What is chickenpox? Chickenpox is an infection caused by the varicella-zoster virus. It is most common in children.


  • Front of Chickenpox and pregnancy fact sheetChickenpox and Pregnancy Fact Sheet (PDF 78KB)
    View, download and print the Chickenpox and Pregnancy Fact Sheet. Chickenpox is an illness caused by the varicella-zoster virus. It is most common in young children but older children and adults who have never had chickenpox can be sick with it as well.

What are the signs and symptoms of chickenpox?

Infection with chickenpox may begin with a mild fever, followed in a day or two by a rash, which may be very itchy.

  • The rash starts with red spots that soon turn into fluid-filled blisters. In a few days, crusts form over the blisters.
  • The chickenpox rash usually appears 14-21 days after exposure to the virus.

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How is chickenpox spread?

  • The chickenpox virus spreads very easily through the air or through direct contact with the fluid from a chickenpox blister.
  • It is highly contagious among people who are not immune and can spread quickly within childcare facilities, schools and families.

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When is it contagious?

  • Chickenpox is contagious usually 1-2 days, and possibly up to 5 days, before the onset of the rash. It remains contagious until 5 days after the onset of the rash or until all the lesions have crusted over, whichever comes first.

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Chickenpox and Pregnancy: The Risk

  • Pregnant women who have never had chickenpox can develop severe illness if they get chickenpox while pregnant.
  • Chickenpox can affect the developing baby if the mother becomes infected in the first half of pregnancy and the newborn baby can develop severe chickenpox disease if the mother has the infection around the time of delivery.

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How do I know if I’m immune to chickenpox?

  • If you have a past history of chickenpox, you will have developed antibodies to protect you from getting chicken pox again.
  • If you can not recall previous infection, you can have a blood test to determine if you have any antibodies to chickenpox. Even if you don’t remember having chickenpox, most people show immune protection when their blood was tested.

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What if I have no immunity, and am exposed to a case of chickenpox?

  • If you are pregnant and have no immunity see your doctor as soon as possible after the exposure.
  • You may be advised to receive an injection of varicella-zoster immune globulin (VZIG) to help prevent severe infection.

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What is Varicella-Zoster immune globulin (VZIG)?

  • VZIG is a blood product that provides immediate protection against chickenpox. It is used in people who have never had chickenpox and have been exposed to someone with chickenpox and are either pregnant or have problems with their immune system.

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What about the chickenpox vaccine?

  • Chickenpox vaccines (Varivax III or Varilrix) (PDF 182KB) should NOT be used during pregnancy.
  • Those who are 12 months to 12 years old receive two doses 3 months apart. Those who are 13 years or older, receive two doses at least 6 weeks apart.
  • Women who do not have protection from chickenpox as determined by the blood test, and are considering a future pregnancy should receive the vaccine. Women should not become pregnant for one month after receiving the second needle. A reliable form of birth control must be used during that time.
  • Chickenpox vaccine is free to children born on or after January 1, 2000 and for high-risk people of all ages who have not had the chickenpox. There is a charge for the vaccine if you do not fit into one of these categories. Discuss the fee with your doctor or a public health nurse at the health unit.

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What about shingles (herpes-zoster)?

  • Shingles is a reactivation of the chickenpox virus that has stayed in the body since the original infection. It results in fluid-filled blisters along the nerve pathway where the virus resides. A person with open sores is contagious for a week after the appearance of these lesions.
  • Shingles is not as contagious as chickenpox but an unprotected person in direct contact with the fluid-filled blisters can get chickenpox. Shingles is not spread through the air.

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Date of creation: February 1, 2013
Last modified on: January 11, 2016


1Public Health Agency of Canada (2013), Canadian Immunization Guide; Evergreen Edition Retrieved from
2Heymann, D. L. (2015). Control of communicable diseases manual (20th ed,). Washington, DC: American Public Health Association.