Are People Who Are Pregnant Immunocompromised?

When you're pregnant you try to eat right, exercise, and stay healthy to keep your baby safe. But you may be worried about how safe you and your baby are during outbreaks of COVID-19. The Centers for Disease Control and Prevention (CDC) strongly urged pregnant people to get the COVID-19 vaccine. Per the CDC, they are more likely to become severely ill with COVID-19 than non-pregnant people.

If you are pregnant, you may be wondering—why? The CDC has strongly urged all Americans over six months to get vaccinated against COVID-19 and particularly stressed how important it is for immunocompromised people to get the shot.

Does the guidance mean that pregnant people are immunocompromised? It's a little more complicated than most people realize. Here's what you need to know.

Your Immune System During Pregnancy

During pregnancy, your body faces the challenge of protecting the fetus while fighting against viruses and bacteria, according to a review from 2021 in Frontiers in Global Women's Health. So, there may be some adaptations that your body goes through to do both of these things.

"During pregnancy, there are many immunological and physiological changes that occur," said health expert Jennifer Wider, MD. "The immune system is often in flux, and as a result, pregnant [people] may be more vulnerable to infections, including viral respiratory infections like COVID-19."

According to the review, those immune changes are perfectly timed with the stages of pregnancy to help protect both you and the fetus while allowing you to carry the fetus to term.

"The maternal immune system adapts and changes, depending on what stage of the pregnancy you're in," said Christine Greves, MD, an OB-GYN at the Winnie Palmer Hospital for Women and Babies. "In the beginning, there's a pro-inflammatory state, which is helpful for implantation. Then it goes into an anti-inflammatory state, which is helpful for the growth of the [fetus]. In the third trimester, it reaches another pro-inflammatory state to prepare for childbirth."

Most of those adaptations are good for both the fetus and the pregnant person. However, some of these changes can also negatively affect the pregnant person. 

According to the 2021 review, high levels of estrogen and progesterone can cause the respiratory tract to swell, making them more susceptible to infections like COVID-19. So, does that mean pregnant people are immunocompromised?

What Does It Mean To Be Immunocompromised?

A person who is immunocompromised has a weakened immune system, according to the National Cancer Institute (NCI). Those people have a lowered ability to fight infections and other diseases and conditions such as human immunodeficiency virus (HIV), cancer, diabetes, malnutrition, and certain genetic disorders. 

Some medicines or treatments, like radiation therapy, organ transplant, and anti-cancer drugs, can also cause immunosuppression.

Are Pregnant People Immunocompromised?

The short answer: Not exactly. 

"It's kind of nuanced," said David F. Colombo, MD, a Michigan-based OB-GYN and division chief of maternal-fetal medicine at Spectrum Health. "The answer is no, but with an asterisk. Your immune system just works differently when you're pregnant."

"I don't think we should officially call pregnant [people] 'immunocompromised' as, for example, [people] who have cancer and are getting chemotherapy, or folks who are born with immunodeficiency diseases," added Mary Jane Minkin, MD, a clinical professor of obstetrics and gynecology and reproductive sciences at Yale School of Medicine. "However, many folks think of pregnant [people] as somewhat immunocompromised because they are 'tolerating' a foreign presence in their uterus." 

A fetus has genes from a different person as well, Dr. Minkin pointed out, and a pregnant person's immune system must tolerate that on an immunological level.

"Pregnant [people] are considered to be a 'special population group' due to the state of the immune system during pregnancy," Dr. Wider said. But while people who are pregnant aren't immunocompromised per se, "a pregnant person's body is undergoing immune system changes and is not operating the same way a non-pregnant person is." 

As a result, "[their] body cannot defend against infections in the same way," added Dr. Wider.

What Does That Mean for COVID-19?

Regarding COVID-19, Dr. Minkin said that pregnant people are susceptible to serious illness for reasons outside their immune response. 

"One problem with [COVID-19] and related illnesses that has nothing to do with the immune system are that pregnant [people] have this 'thing' in their abdomens that pushes up the diaphragm, so lung space is compromised," explained Dr. Minkin. "If pneumonia sets in, they will mechanically have worse problems ventilating."

People with COVID-19 have a higher prevalence of cesarean section (c-section) and premature birth, according to the 2021 review. That may be due to changes caused by the virus in blood circulation in the placenta. Most of these people were asymptomatic or had mild symptoms of COVID-19.

What Can Pregnant People Do To Stay Healthy?

Dr. Colombo stressed the importance of getting vaccinated against COVID-19. "The biggest risk to pregnant [people] right now is catching COVID," Dr. Colombo said. "The vaccine is safe, [COVID-19] is not."

There's also another thing to consider, per Dr. Minkin: "Besides protecting the [pregnant person], there is evidence that [they] will pass on some antibodies to [their fetus]." It's also important to wear a mask when indoors in areas with a substantial or high rate of COVID-19 spread, wash your hands, and practice social distancing, Dr. Wider said. 

"Taking these precautions will go a long way in keeping a [pregnant person] and [their fetus] safe."

A Quick Review

While pregnant people aren't exactly immunocompromised, their immune system works differently than those who are not pregnant. Because of that, they may want to be extra cautious regarding COVID-19. The CDC highly recommended that pregnant people receive their vaccines and booster shots to protect themselves and the fetus.

Dr. Greves advised patients to be "as careful as possible because there are other infections floating around other than COVID-19 or the flu," but added that pregnant people shouldn't panic.

"Recognize that you're doing all you can do and try not to be too anxious about it," Dr. Greves said. "If you're doing all you can, enjoy your life and the beautiful [fetus] growing inside."