Pregnancy and Chickenpox

Chickenpox is caused by a virus called Varicella Zoster Virus (VZV). This virus is very contagious and spread through the air and respiratory system. Usually, a red itchy rash develops that forms blisters and later scabs. It happens 10 to 21 days after being around (exposed) someone with chickenpox. In pregnant women, chickenpox can cause serious harm to the baby.


  • Flu like symptoms develop first.

  • Red rash with blisters.

  • Blisters turn into scabs.


In the pregnant woman:

  • The diagnosis is easily made when the rash and blisters occur.

  • Blood test finding the VZV antigen in the blood.

  • Analyzing fluid from the blisters for the virus antigen.

In the fetus:

  • Ultrasound of the fetus showing abnormalities when the mother has chickenpox called Congenital Varicella Syndrome including:

  • Heart abnormalities.

  • The fetus is filled with fluid (hydrops fetalis).

  • The brain is too small (microcephaly).

  • Problems with the arms and legs developing normally.

  • Slow growth of the fetus.


The mother:

  • Antiviral medication (acyclovir) is given by mouth within 24 hours of the rash. It lessens the symptoms, the rash and formation of new blisters. This medicine does not harm the baby.

  • Acyclovir is given through the mother's vein if the mother develops pneumonia or encephalitis.

  • The acyclovir does not prevent the baby from being affected by the virus.

The baby:

  • VariZoster Immine Globulin (VariZIG) is given to the mother if she developed chickenpox 5 days before delivery. This medicine is given to the newborn two days after delivery.

  • Acyclovir is given through the baby's vein if the newborn develops chickenpox within the first 2 weeks of delivery.

If a pregnant woman gets chickenpox in the second half of the pregnancy, the baby usually is fine because the mother produces antibodies that cross the placenta into the baby. These antibodies protect the baby.


  • Avoid anyone with chickenpox when pregnant.

  • Do not scratch the rash or pick the scabs. It can cause scarring.


  • You develop flu-like symptoms, a rash, and blisters.

  • You want to get pregnant but do not know if you had chickenpox.

  • You are pregnant and one of your children develops chickenpox.

  • You develop chickenpox when pregnant and want a genetic counselor.


  • You have chickenpox and develop uterine contractions.

  • You have chickenpox and you begin leaking fluid from the vagina.

  • You have chickenpox and develop a temperature of 100° F (37.8° C) or higher.

  • You have chickenpox and develop shortness of breath.

  • You have chickenpox and you develop severe headache.