Chickenpox is a common childhood disease that causes an itchy, uncomfortable rash and red spots or blistering (pox) all over the body. Although it is highly contagious, and very uncomfortable, it is rarely considered serious when contracted as a child. However, if contracted by pregnant women or newborns, whose immune systems may be compromised, chickenpox may cause real problems.
The first symptoms of chickenpox will typically begin appearing 14 to 16 days after exposure to someone with the disease, with a range of 10 to 21 days. It’s common to experience mild illness, with headache, tiredness, fever, and cough for several days before the rash appears. In some children, however, the rash may be the first sign of the disease.
The rash usually first appears on the head (including on the face and in the hair), chest, and back, and then spreads quickly, with as many as 250 to 500 fluid-filled blisters appearing on the rest of your body. Blisters are usually concentrated on the chest and back, but may also appear on eyelids, inside of the mouth. The spots start as red, itchy lumps, which then become blisters before crusting over. This process usually takes one to two days, with new spots continuing to come in waves for up to seven days. Typically it takes about 10 days after the first symptoms appear for all blisters to crust over, and the patient be considered well enough to resume normal activities.
The disease, caused by the varicella-zoster virus, can be passed from person-to-person either by direct contact (e.g. touching the fluid in the blisters), or indirect contact (e.g. sneezing or coughing, or touching something that has touched the fluid from the blisters). Any child or adult who has never had chickenpox or been vaccinated against it, is at risk for contracting the disease.
A person with chickenpox is contagious from the beginning of the illness (up to two days before the spots first appear) until about five days after the first spots appear. As long as no new blisters are appearing, and all spots present on the skin have crusted over, the person is no longer contagious.
Until the varicella vaccine was licensed in 1995, chickenpox infection was highly common, and almost everyone had been infected as a child. Now, two doses of the vaccine are recommended for children age 12 months or older, teens and non-immune adults.
Chickenpox Prior To Pregnancy
You probably don’t need to worry about chickenpox if you’ve had it before or have had the chickenpox vaccine, as both will help give you immunity to contracting chickenpox. According to the March of Dimes, 90% of pregnant women are immune to chickenpox.
If you are unsure whether you’ve had chickenpox before and are concerned you may have been exposed, you should contact your doctor. He or she will perform a blood test that shows whether you’ve had the disease.
If you’ve never had chickenpox, or have not been vaccinated, it is important to get immunized prior to conceiving. Based on guidelines from the Society of Obstetricians and Gynecologists of Canada, women who choose to be vaccinated should do so at least four weeks before trying to conceive. Since chickenpox immunization is not an option during pregnancy, it is imperative to check your immunity prior to conceiving.
Your only other option is to avoid exposure to chickenpox, which can be difficult since chickenpox symptoms only begin to show several days after infection. It’s wise to steer clear of anyone who’s not immune and has come in contact with an infected person in the past three weeks (other moms, for example), or anyone with flu-like symptoms, particularly if there has been a local outbreak. You should also avoid anyone with shingles.
Chickenpox During Pregnancy
Chances are your baby will be fine, but chickenpox during pregnancy can hurt your baby depending on when you become infected. Should you contract chickenpox during the first 20 weeks of your pregnancy, there is a slight risk (less than 2%) your baby may develop congenital varicella syndrome. The risk is highest if you’re infected between weeks 13 and 20.
Congenital varicella syndrome is a group of birth defects that can include:
- Problems with muscles and bones
- Abnormally small head
- Malformed limbs
- Vision problems or blindness
- Learning problems
In your third trimester, after 20 weeks of pregnancy, birth defects from chickenpox are very rare. About five days after you come down with the virus, your body produces antibodies that pass to your baby through the placenta, which provide protection his/her own immune system can’t provide.
Your baby is at most risk from exposure to chickenpox about five days before you deliver until two days after delivery. During this exposure period, they won't have time to receive antibodies from you. The March of Dimes estimates there is a 30% chance your baby could get a serious, even deadly, form of the infection in such cases.
Chickenpox Treatment During Pregnancy
If you think you have chickenpox, or start to show symptoms, it’s imperative your contact your doctor right away. Your doctor should make arrangements to see you privately to prevent inadvertently infecting other people.
Your doctor is likely to prescribe acyclovir, an antiviral drug that kills infections caused by viruses, and has been shown to safe during pregnancy. Should you show signs of pneumonia, you may require hospitalization to avoid any escalation of symptoms. Even if your symptoms remain relatively mild, it’s important to contact your physician so you can be carefully monitored and treated with higher doses of acyclovir through an IV.
If you have chickenpox around the time your baby is born, your doctor will treat your baby with medicine containing chickenpox antibodies. If the medicine fails to prevent chickenpox or make it less severe, your doctor will administer an antiviral like acyclovir.