Chickenpox during pregnancy

Chickenpox (also called varicella) is a common infection in children. It can be harmful to your unborn baby or newborn if you get it during pregnancy. But you don’t need to worry about getting chickenpox if you:

  • Had chickenpox before
  • Had a vaccine for chickenpox. A vaccine is a medicine you get that protects against certain diseases.

In either of these cases, you’re immune to chickenpox. Immune means being protected from an infection. If you're immune to an infection, it means you can't get it. About 9 out of 10 pregnant women (90 percent) are immune to chickenpox.

Many women don’t know if they’re immune to chickenpox. If you’re not sure, talk to your health care provider about chickenpox during your first prenatal visit.

What is chickenpox?
Chickenpox is caused by a virus. People usually get it during childhood. Its symptoms include an itchy rash, blisters and fever. These symptoms show up about 2 weeks after you get the chickenpox virus. The infection usually isn’t dangerous in children. But 1 to 2 out of 10 pregnant women (about 10 to 20 percent) who get chickenpox get a dangerous form of pneumonia (a kind of lung infection).

You can get chickenpox by being in contact with someone else’s chickenpox rash. It’s also spread through the air when someone with chickenpox coughs or sneezes. An infected person can spread chickenpox starting 1 to 2 days before the rash appears and until the rash stops spreading and is covered by dry scabs. This usually is about 5 days after the rash starts.

How do you know if you have chickenpox?
Tell your provider right away if you come into contact with someone who has chickenpox.

Your provider can tell you if you have chickenpox by doing a physical exam. Sometimes, your provider takes a swab of the rash and sends it to a laboratory for testing to be sure it’s chickenpox.

Can chickenpox hurt your baby during pregnancy?
Yes, but most likely your baby will be born healthy. But some babies may get congenital varicella syndrome. This is a group of birth defects that can include:

  • Scars
  • Problems with muscles and bones
  • Arms or legs that are paralyzed or not formed correctly
  • A head that’s smaller than normal
  • Blindness
  • Seizures
  • Learning problems

Only about 1 or 2 out of 100 babies (1 to 2 percent) whose mothers had chickenpox during the first 20 weeks of pregnancy get congenital varicella syndrome. Your provider can do an ultrasound to check for some birth defects caused by chickenpox.

Birth defects are very rare when you get infected with chickenpox after 20 weeks of pregnancy. But your baby could have problems with his central nervous system (brain and spinal cord) if you get infected in the third trimester of pregnancy.

Infection after 20 weeks of pregnancy also may cause shingles in your baby during the first 1 to 2 years of life. Shingles (also called herpes zoster) is an infection caused by the same virus that causes chickenpox. A person with shingles has painful clusters of blisters that usually appear on a small area of the body. Shingles doesn’t seem to cause birth defects or infections in your baby.

Can chickenpox hurt your newborn baby?
It depends on when the infection happens. If you get a chickenpox rash about 1 to 3 weeks before giving birth, there’s some chance that you can pass the infection to your baby. But if that happens, the infection is usually mild.

But if you get a chickenpox rash the week before you give birth or within a couple days after giving birth, there is up to a 3 in 10 chance (30 percent) that your baby will get a serious, even deadly, form of the infection.

How is chickenpox treated during pregnancy?
If you get chickenpox while you’re pregnant, your provider gives you an antiviral called acyclovir to help with the symptoms. An antiviral is a medicine that kills infections caused by viruses. Studies have shown that this medicine is safe during pregnancy. If you start to get any signs of pneumonia, you need to be hospitalized and treated with a higher amount of antivirals through an IV (when medicine is given through a needle into a vein.).

How is chickenpox treated in your newborn baby?
If your newborn has the serious form of the infection, your provider treats your baby right after birth with medicine that has chickenpox antibodies. Antibodies are cells in the body that fight off infection. The medicine can help prevent chickenpox in your baby or make it less dangerous.

If your baby still gets chickenpox after getting treated, she can be treated with an antiviral like acyclovir.

How can you avoid chickenpox during pregnancy if you aren’t immune?
First, get a blood test to find out if you’re immune to chickenpox. Get tested if you’re pregnant or planning to get pregnant. If you’re not immune, you can get a vaccine. It’s best to wait 1 month after the vaccine before getting pregnant.

If you’re already pregnant, don’t get the vaccine until after you give birth. In the meantime, avoid contact with anyone who has chickenpox or shingles.

If you’re not immune to chickenpox and you come into contact with someone who has it, tell your provider right away. Your provider can treat you with medicine that has chickenpox antibodies. It’s important to get treatment within 4 days after you’ve come into contact with chickenpox to help prevent the infection or make it less serious.

Also, tell your provider if you come in contact with a person who has shingles. Your provider can treat you with the antiviral acyclovir.

Can you get chickenpox from a child who just had a vaccine?
Not usually, but it can happen if a child gets sores after having the vaccine. Sores can appear around the area where the child got the vaccine. Make sure your children are vaccinated for chickenpox at ages 12 to 15 months and at 4 to 6 years. Your chances of getting chickenpox from a child who recently had a vaccine are much lower than the chances of getting it from a child who doesn’t have the vaccine.

What are the chances of getting chickenpox during pregnancy?
About 1 out of 1,000 pregnant women in the United States gets chickenpox. Most children get chickenpox vaccines, so the chances of getting it are becoming even lower.

Nine out of 10 pregnant women (90 percent) who aren’t immune to chickenpox get the infection when someone else in their home has it.

Last reviewed November 2011

See also: Vaccinations and pregnancy

Most common questions

What is mononucleosis?

Mononucleosis (also called mono) is an infection usually caused by the Epstein-Barr virus (EBV). It’s sometimes caused by another virus called cytomegalovirus (CMV). EBV and CMV are part of the herpes virus family. Mono is most common in teenagers and young adults, but anyone can get it. Mono is called the “kissing disease” because it’s usually passed from one person to another through saliva. In addition to kissing, it can also be passed through sneezing, coughing or sharing pillows, drinks, straws, and toothbrushes.

You can have mono without having any symptoms. But even if you don’t get sick, you can still pass it to others. Symptoms can include:

  • Achy muscles
  • Belly pain
  • Fatigue (feeling tired all the time)
  • Fever
  • Sore throat
  • Swollen glands in your neck

If your symptoms don’t go away or get worse, tell your health care provider. He’ll most likely do a physical exam and test your blood to find out for sure if you have mono.

There’s no vaccine to prevent mono. There’s also no specific treatment. The best care is to take it easy and get as much rest as you can. It may take a few weeks before you fully recover.

Can Rh factor affect my baby?

The Rh factor may be a problem if mom is Rh-negative but dad is Rh-positive. If dad is Rh-negative, there is no risk.

If your baby gets her Rh-positive factor from dad, your body may believe that your baby's red blood cells are foreign elements attacking you. Your body may make antibodies to fight them. This is called sensitization.

If you're Rh-negative, you can get shots of Rh immune globulin (RhIg) to stop your body from attacking your baby. It's best to get these shots at 28 weeks of pregnancy and again within 72 hours of giving birth if a blood test shows that your baby is Rh-positive. You won't need anymore shots after giving birth if your baby is Rh-negative. You should also get a shot after certain pregnancy exams like an amniocentesis, a chorionic villus sampling or an external cephalic version (when your provider tries to turn a breech-position baby head down before labor). You'll also want to get the shot if you have a miscarriage, an ectopic pregnancy or suffer abdominal trauma.

I had a miscarriage. How long should I wait to try again?

Before getting pregnant again, it's important that you are ready both physically and emotionally. If you don't need tests or treatments to discover the cause of the miscarriage, it's usually OK for you to become pregnant after one normal menstrual cycle. However, it may take longer for you to feel emotionally ready to be pregnant again. Everyone responds differently to a miscarriage. Only you will know when you are ready to try to get pregnant again.

Are gallstones common during pregnancy?

Not common, but they do happen. Elevated hormones during pregnancy can cause the gallbladder to function more slowly, less efficiently. The gallbladder stores and releases bile, a substance produced in the liver. Bile helps digest fat. When bile sits in the gallbladder for too long, hard, solid nuggets called gallstones can form. The stones can block the flow of bile, causing indigestion and sometimes serious pain. Staying at a healthy weight during pregnancy can help lower your risk of gallstones. Exercise and eating foods that are low in fat and high in fiber, like veggies, fruits and whole grains, can help, too. Symptoms of gallstones include nausea, vomiting and intense, continuous abdominal pain. Treatment during pregnancy may include surgery to remove the gallbladder. Gallstones in the third trimester can be managed with a strict meal plan and pain medication, followed by surgery several weeks after delivery.

©2013 March of Dimes Foundation. The March of Dimes is a non-profit organization recognized as tax-exempt under Internal Revenue Code section 501(c)(3).