COVID vaccine and pregnancy: Why it's recommended

The CDC, the American College of Obstetricians and Gynecologists (ACOG), and the Society for Maternal-Fetal Medicine (SMFM), among many other medical organizations, all recommend that pregnant women receive the COVID-19 vaccine. These organizations also recommend that pregnant and postpartum women receive a booster dose of the COVID-19 vaccine, following the completion of their original COVID-19 vaccine or vaccine series. 

Although the majority of pregnant women who get COVID-19 appear to have healthy pregnancies and babies, they're at higher risk for severe illness and ICU admission, intubation, and death, as well as pregnancy-specific complications such as preterm birth and fetal growth restriction.

Pregnant women who get COVID-19 are three times more likely to require admission to the hospital and to the ICU than women of similar age who aren't pregnant. The risk of death from COVID-19 is 1.7-fold higher for pregnant women than for non-pregnant people.  

Studies indicate that COVID vaccines are safe and effective in pregnant and breastfeeding women, and nursing moms are likely to produce antibodies that can pass protection to babies.

Important: Though there have been widespread rumors on social media, there's no evidence, or even a plausible basis for speculation, that getting a COVID-19 vaccine affects fertility or causes miscarriage. And there's no need to put off getting a vaccine because you're trying to get pregnant.

Here's what we know so far:

  • Tens of thousands of pregnant and breastfeeding women have already had a COVID-19 vaccine. The CDC is monitoring many of these women to see if any safety concerns arise. The FDA has also asked the drug companies to file regular reports on the safety of the vaccines, including their use in pregnant women. 
  • So far more than 139,000 pregnant women have used the CDC's v-safe program to self-report their condition after getting the vaccines, and their side effects don't differ from those in the general population. Also, in vaccinated pregnant women registered with the program, adverse pregnancy outcomes (like stillbirth, preterm birth, and small size for gestational age) fell within normal ranges expected for pregnant women overall.
  • In a preliminary study of more than 35,000 women who received a COVID-19 vaccine during or right before pregnancy, the CDC found no evidence that the Moderna or Pfizer vaccines pose risks to pregnant women. The study was published in The New England Journal of Medicine and is based on self-reported data from women who received the vaccines between December 14, 2020 and February 28, 2021. Participants reported similar side effects as non-pregnant people, and their rates of miscarriage, babies born prematurely or at low birth weight, and birth defects were no higher than those before the pandemic.
  • A study involving 84 pregnant and 31 breastfeeding women published in the American Journal of Obstetrics and Gynecology in March, 2021, found that the Moderna and Pfizer vaccines were highly effective at producing antibodies in these women, and the antibodies were passed to their babies through the placenta and breastmilk.
  • Other types of vaccines have been given to pregnant women for decades and have been overwhelmingly safe.

COVID vaccine and breastfeeding

If you're breastfeeding, it’s also recommended that you get a COVID-19 vaccine. As with pregnant women, research on the safety and effectiveness of the vaccines in breastfeeding women is ongoing, but current findings show the vaccines protect against severe illness, and pose no harm to you or your baby.

Vaccine components won't make it into breast milk. As the vaccine is composed of mRNA (cellular instructions to build a protein) within a little fat bubble, the vaccine injected into your arm won't have a chance to travel through your bloodstream and into your milk. It would be absorbed into your cells long before making it there.

On the flip side, early research shows that antibodies produced by the vaccine do make it into breastmilk and are passed on to the baby, potentially protecting the child from COVID-19. Several other vaccines, such as the flu vaccine, are proven to have this effect.

Does the COVID vaccine protect against new variants of the virus?

Current research shows the COVID-19 vaccine is very effective at preventing serious illness, including hospitalizations, from variants. (A variant means that the virus has a mutation that distinguishes it from another virus.) Further studies will help us understand any differences in vaccine coverage for new variants.

There are multiple variants of the COVID-19 virus. The main concern right now is the B.1.617.2 variant called the Delta strain, as well as the  B.1.1.529 Omicron strain, which was first detected in November 2021 in South Africa. These strains are highly contagious when compared to the original virus and experts emphasis that the unvaccinated are most at risk.

COVID vaccine side effects

Serious side effects from the COVID-19 vaccines are extremely rare, and some people experience no side effects at all. But it's common to have mild vaccine side effects. These include:

  • Swelling, redness or pain at the injection site
  • Fever
  • Headache
  • Fatigue
  • Muscle pain
  • Chills
  • Nausea

You're very unlikely to develop any long-term side effects from the COVID-19 vaccines. According to the CDC, vaccine monitoring historically shows that if side effects do happen, it's within 6 weeks of receiving a vaccine dose. Before authorizing the vaccines, the FDA required drugmakers to monitor clinical trial participants for at least 8 weeks after they received the final dose.

Is the COVID vaccine safe?

The currently authorized vaccines have proven safe and effective so far for adults, and research indicates they are safe for teens, pregnant women, breastfeeding moms, and those hoping to become pregnant. Millions of people across the United States and the world have received the vaccines safely. The vaccines went through a rigorous clinical trial process before being approved, and the CDC continues to monitor their safety.

However, some people have experienced serious side effects. These are extremely rare, but worth knowing about and watching for.

Blood clots

Use of the Johnson & Johnson vaccine was paused on April 13 because of concerns it may be linked to a very rare blood-clotting disorder that affected 15 women between ages 18 and 49. The CDC and Food and Drug Administration lifted the pause on April 23, saying that the vaccine's known and potential benefits outweigh its known and potential risks in people 18 and older.

The CDC says that women younger than 50 years old especially should be aware of the "rare risk of blood clots with low platelets after vaccination," associated with the Johnson & Johnson vaccine. The CDC also emphasized that the Moderna and Pfizer vaccines don't carry this risk.

Keep in mind that this serious side effect is exceedingly rare. About 8 million people have gotten the Johnson & Johnson vaccine without experiencing it. But if you received the vaccine within the past three weeks and develop severe headache, abdominal pain, leg pain, or shortness of breath, seek medical care right away.

Heart inflammation

There have also been rare reports of inflammation of the heart – called myocarditis and pericarditis – following vaccination with the Pfizer and Moderna vaccines, particularly in teens and young adults. These cases occurred primarily in boys ages 16 and older, and within a few days of receiving the second vaccine dose. Most patients recovered quickly after getting treatment and rest.

Health authorities are monitoring these reports. The CDC continues to recommend COVID-19 vaccinations for everyone ages 12 and older, and says the benefits of being vaccinated outweigh the risk of heart inflammation. However, seek medical care if your child experiences chest pains, shortness of breath, or has a fast or fluttering heartbeat within a week after receiving a COVID-19 vaccine.

Allergic reactions

Between 2 and 5 people out of every million who get a COVID-19 vaccine experience a serious allergic reaction. In most cases, these reactions can be treated immediately with medications, and people fully recover. However, because some people are more at risk of a severe vaccine reaction than others, the CDC recommends the following:

  • If you've had an immediate allergic reaction to any other kind of vaccine or injectable therapy in the past (even if it wasn't severe), ask your doctor whether you should get a COVID-19 vaccine.
  • If you have an allergic reaction to your first shot of a COVID-19 vaccine, ask your doctor if you should get a different type of vaccine.
  • If you're allergic to polyethylene glycol (PEG), don't get the Pfizer or Moderna vaccines. If you're allergic to polysorbate, the Johnson and Johnson vaccine is also not for you.
  • You can get the vaccine if you have a history of severe allergic reactions unrelated to vaccines (such as allergies to pets, food, and latex).

Symptoms of allergic reaction include hives, pale skin, swelling in the face or mouth, and wheezing or trouble breathing. They do not include vaccine side effects such as fever, chills or fatigue, which tend to occur within a few days after vaccination.

Read more about pregnancy and the coronavirus, and COVID-19 in babies, toddlers, and young children.