Which Vaccines to Get—and Avoid—While Pregnant

If you’re pregnant, you have a lot to do to stay healthy for you and your unborn baby—take a daily prenatal vitamin, eat a healthy diet and attend routine checkups, to name a few. It’s also critical to stay up to date on your vaccinations, since being pregnant puts you at a higher risk of severe illness from some diseases.

UNC Health maternal-fetal medicine specialist Johanna Quist-Nelson, MD, breaks down which vaccines you should receive—and avoid—during pregnancy.

Vaccines You Need While Pregnant

If you are expecting a baby or planning a pregnancy, talk to your doctor about getting the following vaccinations:

  • Influenza (flu): You should get a flu shot once during each flu season, which typically runs from October through May. This is especially important if you are pregnant.

“This recommendation is supported by robust data that show good outcomes for both moms and babies,” Dr. Quist-Nelson says. “Pregnant patients have a higher risk of ending up in the intensive care unit or even dying from influenza compared to nonpregnant patients of the same age. Newborns also don’t do well with the flu and can’t be vaccinated, so when the patient gets the flu shot, it is protecting both.”

Getting the flu shot covers you and your unborn baby for the duration of that year’s flu season. In other words, if you were vaccinated in October and became pregnant in December, you do not need to get another shot, Dr. Quist-Nelson says. The antibodies will transfer to the fetus through the placenta, which is the organ that develops in your uterus to provide nutrients and oxygen to the baby.

When the flu vaccine is given with a nasal spray it is a live vaccine. This means it contains a gentle strain of the illness that doesn’t affect adults but poses a theoretical risk to the baby, Dr. Quist-Nelson says. Although this is rare, check with your provider that the flu shot you are getting is not live. If you receive the flu shot as an injection, it is safe to assume the vaccine is not live.

  • Tetanus, diphtheria and pertussis (Tdap): The Tdap vaccine protects against tetanus, diphtheria and pertussis (whooping cough). Pertussis causes violent coughing and poses the biggest risk of severe, life-threatening complications to infants, Dr. Quist-Nelson says. According to the Centers for Disease Control and Prevention, all three conditions can be extremely serious, and even fatal, in babies.

The Tdap vaccine is administered between weeks 27 and 36 of pregnancy to protect the fetus, since newborns cannot be immunized, Dr. Quist-Nelson says.

The CDC recommends that children be vaccinated against these three conditions starting at 2 months old. The vaccines have been combined so children do not need to get so many individual shots.

  • COVID-19: It is critical that pregnant women receive a COVID-19 vaccine and associated booster shot because they are at a higher risk of severe illness from the virus, Dr. Quist-Nelson says.

Although the data is newer, it is quite robust and shows that the vaccines are safe for mother and baby, she says.

“COVID-19 in pregnancy is very unsafe, and we know that pregnant patients do a lot worse than nonpregnant patients of the same age. It is really important to protect yourself and your unborn baby by receiving the vaccine. Hundreds of thousands of pregnant patients have gotten the COVID-19 vaccine, and it has shown to protect them from ICU admissions and severe morbidity,” Dr. Quist-Nelson says. “Under the current guidelines, babies will not be able to be vaccinated until they are 5 years old, so mom getting vaccinated gives the unborn baby the protection needed after birth.”

As for the long-term effects of the vaccines, Dr. Quist-Nelson says there has never been a vaccine that has shown negative long-term effects. They simply provide a way for patient and baby to mount an immune response in the event that they are exposed to COVID-19, she says.

The CDC says the Pfizer-BioNTech or Moderna vaccines are preferred over Johnson & Johnson/Janssen for pregnant patients, but the J&J vaccine may be considered in some situations and is better than not being vaccinated.

Vaccines Pregnant Patients Should Not Receive

Measles, mumps, rubella (MMR) and varicella (chickenpox) are both live vaccines that pose a theoretical risk of transmitting the disease to the fetus. It is recommended to avoid them during pregnancy.

These vaccines are often administered to unvaccinated patients after delivery out of an abundance of caution, Dr. Quist-Nelson says. The reason for giving the vaccines after delivery to those who aren’t immune is to protect them from chickenpox or rubella in the next pregnancy. Both chickenpox or rubella infections can cause pregnancy complications or miscarriage. MMR and varicella vaccines are safe for breastfeeding women. Adults who aren’t pregnant and haven’t had chickenpox should also receive the varicella vaccine, according to the CDC.

The CDC says children can start to receive MMR and varicella vaccines when they are 12 to 15 months old. Both series include two doses.

How Mom’s and Baby’s Immune Systems Work Together

Unborn babies and newborns have immature immune systems, Dr. Quist-Nelson says. In the womb and for the first few months of life, they have more dependence on antibodies that their mothers deliver through the placenta and breast milk.

“The vaccines are amazing because they boost the mother’s antibodies, which will cross the placenta to reach the fetus. They have also shown to be present in breast milk. We have studies showing babies are born immune to both the flu and COVID-19 if mom received the vaccines while pregnant,” Dr. Quist-Nelson says. “This makes pregnancy an ideal time to give those recommended vaccines.”

Ask your doctor if you are up to date on vaccinations. Need a doctor? Find one near you.