Can a pregnant woman with chickenpox transmit the infection to her baby?

Yes, a pregnant woman with chickenpox (varicella) can transmit the infection to her baby. This is a complex medical condition that requires immediate and specialized medical care [4]. While most pregnant women have prior immunity to the virus, a primary infection during pregnancy can pose health risks to both the mother and the fetus. Chickenpox is a highly contagious disease caused by the varicella-zoster virus, and if a pregnant woman contracts it, the risk of transmission to the baby depends significantly on the timing of the infection during pregnancy [3], [4].

How does the timing of the infection affect the baby?

The risk of transmission and the impact on the baby vary based on the stage of pregnancy in which the infection occurs:

• Up to the 28th week of pregnancy: There is a very small probability (less than 1 in 100) of specific impacts on the fetus, and the case is monitored through specialized testing [4].
• Between week 28 and 36: The virus may remain in the baby's body without showing immediate symptoms, but it can reactivate later to cause shingles (herpes zoster) in the early years of life [4].
• In the last four weeks before delivery: If the mother develops chickenpox during this period, about 1 in 4 babies will contract it. However, maternal antibodies transferred to the baby may help protect them [4].
• At or immediately after birth (within 7 days of the mother's rash appearing): The baby is at risk of severe chickenpox, especially if the baby is born within 7 days of the mother's chickenpox rash appearing, or if the mother contracts the infection during the first week postpartum. In these cases, the baby is given varicella-zoster immune globulin (VZIG) and treated with an antiviral medication such as acyclovir, and they are closely monitored after birth [4].

Why is an infection during pregnancy considered an emergency?

Pregnant women are considered to be at higher risk for severe chickenpox complications, such as pneumonia or hepatitis, which directly affect the stability of the pregnancy's health status [4]. Additionally, compromised immunity or certain underlying health conditions in the mother may increase the severity of the illness. It is crucial to contact a doctor immediately if you have been exposed to someone with chickenpox or if a rash appears. If the pregnant woman is at 20 weeks of gestation or more, antiviral treatment such as acyclovir may be administered within 24 hours of rash onset to reduce the severity of symptoms and risks [4].

Important preventative steps

If you are planning to become pregnant or are already pregnant, prevention is the best way to protect yourself and your baby. The chickenpox vaccine cannot be given during pregnancy, so it is highly recommended to check your immunity before planning a pregnancy [4]. In the absence of immunity, you should avoid any contact with individuals who have chickenpox or shingles and consult a doctor to undergo necessary tests or receive recommendations on protection from the virus [4]. For more general information on symptoms and measures, you can view our article on Chickenpox (Varicella): Symptoms, Prevention, and Home Treatment (Arabic).

Always remember to avoid using aspirin to treat chickenpox, as it can cause Reye's syndrome, a serious condition [2]. See a doctor immediately if you notice symptoms such as shortness of breath, a very high fever, or an unusual rash [4].

Medical references

• Chickenpox
• About Chickenpox
• Chickenpox and pregnancy | RCOG