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Maternal pregnancy complications


Chickenpox is primarily a childhood disease. Among adults, 95% of the population is immune.

Two days before the appearance of the first vesicles (blisters), a child is already contagious.


  • Risks for the motherContracting chicken pox during pregnancy can be very dangerous. Although this disease is generally benign in childhood, it can cause serious pulmonary disorders like pneumonia in adults. A pregnant women with an infection must be closely monitored by her doctor and sometimes hospitalized.
  • Risks for the fetus
    Chickenpox can also affect the fetus. The fetus is particularly vulnerable during two periods:
    • Before the 28th week.
      There is a risk of congenital chickenpox (in utero infection) which is very dangerous but rare (less than 2% of cases). Affected children can suffer from growth delays, ocular defects, scarring, and brain damage.
    • During the week preceding or the month following delivery.
      There is a risk of infection for the newborn before it can be protected by the antibodies of the mother.


If a pregnant woman is not sure she has had chickenpox, she should tell her doctor, who will recommend a blood test for the presence or absence of relevant antibodies. If the test confirms that the patient has never had chicken pox, a vaccine is advised after she has given birth.

Because chickenpox is very contagious, a pregnant woman should not be around people with the disease if she has no immunity against it.

It should be kept in mind that a person with chicken pox is contagious two days before the appearance of blisters. If a pregnant woman has been in contact with a contagious person, it is important that she meet with her doctor as soon as possible. Preventive treatments, given early, may reduce the risk of infection.

Treatment and follow-up care

If a pregnant woman contracts chicken pox, the doctor should closely monitor fetal development with ultrasound scans. He or she may suggest an amniocentesis to assess the risk of fetal infection.

Page by

Joanne Moreau
Dr Isabelle Boucoiran

About this page
Updated on 1/25/2021
Created on 12/19/2017
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