Should pregnant women get vaccinated against COVID-19? The question is keeping some expectant couples up at night.
Guidance from public health officials has been conflicted and cautious to the point of being noncommittal—that’s one big reason for the hesitancy. For instance, the World Health Organization initially advised that only pregnant women at high risk of COVID-19 exposure or with a separate underlying condition should get the vaccine; then the WHO revised the guidance to reflect the higher risk pregnant women face of getting severe COVID and the increased risk of pre-term birth. But it added a qualification: the available data was “insufficient to assess vaccine efficacy or vaccine-associated risks in pregnancy,” even though “animal studies showed no harmful effects in pregnancy.” An independent advisory committee of the U.S. Centers for Disease Control and Prevention suggested that pregnant women consider getting the shots “after consulting with their physician.”
It’s no wonder pregnant women and their partners are confused.
The larger problem, of course, is a lack of data: pregnant women were excluded from clinical trials for COVID-19 vaccines. With no data on the impact of the vaccines on developing fetuses, many pregnant couples have opted for a wait-and-see approach. They may not realize, though, that in recent months evidence has continued to mount suggesting that pregnant women are in fact at greater risk of developing severe COVID-19 symptoms. By opting to delay vaccinations, they may be putting themselves and their babies at risk.
To find out what pregnant women should know about the vaccines, Newsweek spoke with Dr. Denise Jamieson, an expert on infectious disease and pregnancy who has long studied the thorny issues around vaccinating pregnant women. Dr. Jamieson, chair of the Department of Gynecology & Obstetrics at Emory University School of Medicine, is a member of the COVID-19 working group of the American College of Ob-Gyns, which helped push the WHO to revise its COVID-vaccine guidance. She has been a practicing obstetrician at Atlanta’s Grady Memorial Hospital for more than 20 years and she worked for the CDC for two decades on infectious diseases in pregnancy, studying HIV, influenza, Ebola, Zika and now COVID-19.
Newsweek: In addition to your official roles advising on public health, you are a practicing obstetrician. What are you advising your patients to do?
Dr. Jamieson: In general, I’m recommending for my pregnant patients that they get vaccinated. But they should make sure that all their questions with their healthcare provider are answered and that they’re comfortable before getting vaccinated. The benefits of avoiding COVID, which we know particularly are bad and particularly with a pregnancy, outweigh any theoretical risks of the vaccines. [But] there is a lack of safety data.
What are you basing that recommendation on?
We now know that pregnant women are more likely to have severe disease, if they get COVID. They’re more likely to be hospitalized. They’re more likely to require care in an intensive care unit. They’re more likely to be intubated and they’re more likely to die. We know that from an accumulating body of evidence. The best evidence we have is a very large report from the Centers for Disease Control and Prevention which reported tens of thousands of cases that include pregnant women. When you compare pregnant women to non-pregnant women of the same age and adjust for [medical] risk factors, it looks like pregnancy in and of itself increases your risk for severe disease.
Why would pregnant women be more vulnerable to COVID-19?
It’s not surprising. It’s very similar, in this respect, to other respiratory diseases, like influenza. We know that influenza is more severe in pregnant women for a variety of reasons. First of all, there are complicated, complex changes in the immune system during pregnancy—a fetus is basically like a graft that your body doesn’t reject.
There are also changes in the respiratory system. Basically, as the uterus grows, there’s less room for your lungs, and your lungs become more compressed. Some respiratory illnesses, such as influenza, can be worse in pregnancy. We’ve known that for a long time. We were concerned early on that there would be an increased risk of COVID-19, but it just took us a while to sort it all out. Now there’s a fairly compelling body of evidence that suggests pregnant women are more likely to have severe disease if they get COVID-19.
What impact would that have on the developing fetus?
It looks like COVID-19 can be transmitted from the mother to the fetus, if the mother is infected, but it doesn’t look like that happens very often. The more severe risk is if the mother is sick, particularly severely ill around the time of delivery, the baby often does not do as well. Although all studies are not consistent, it looks like there may be an increased risk of preterm birth. We also know that if a woman is intubated in the intensive care unit, then her baby is not going to do as well either. Preterm babies are at an increased risk for all sorts of problems: their lungs don’t develop correctly, their eyes may be affected—multiple systems may be affected for babies who are born premature.
What’s the fear about giving vaccines to pregnant women? Are you concerned the vaccine might harm the fetus?
The issue is that the vaccines were not thoroughly tested in the pre-approval stages. Pregnant women were excluded from clinical trials, so we have very limited safety and efficacy data. We don’t know if the vaccines work as well in pregnant women as non-pregnant ones. More important, we don’t have good safety data. One reason why most obstetricians are relatively comfortable with offering the vaccine to pregnant women is that vaccines overall have a good track record of safety in pregnancy. We routinely give vaccines like influenza and Tdap. In the case of influenza, we recommend vaccines for pregnant women and have for many decades.
We don’t give live vaccines—vaccines that contain live virus like measles, mumps, and rubella or smallpox. There was a problem with the smallpox vaccine—it can cross the placenta, infect the baby, and then the baby can have adverse effects. But the COVID-19 vaccines are not live viral vaccines—none of them are.
Why is there a lack of safety data?
Aside from COVID-19 vaccinations, in general, pregnant women are often excluded from clinical trials that study new medications or new vaccines, because everyone’s worried about the fetus. Basically, it’s easier to exclude pregnant women so that you don’t have to worry about the effects on the fetus.
Some people are concerned about the risks of conducting research trials with a developing fetus involved. What they don’t realize is there are also risks of developing interventions that then can’t be offered to pregnant women—there are risks to not getting a vaccine. For decades we’ve been saying, “Please include pregnant women in clinical trials so that they’re not excluded when the lifesaving interventions are introduced.” Yet we have continued to exclude pregnant women because it’s easier and less complicated.
That’s what happened this time. Whenever a new pathogen comes along, the medical community acts surprised and wonders what to do with pregnant women. We need to prepare better to thoughtfully include pregnant women in trials earlier on and to think about these pregnancy issues in advance of the next pathogen that emerges.
What has past experience with other pandemics taught us?
Each one is a little bit different. Zika was sadly remarkable in that it had a very specific pattern of congenital defects—it was like the congenital rubella of decades ago, which was a devastating condition. Zika was a very mild disease in most people and no one really thought that much about it, until this pattern of birth defects was recognized.
The sad story about Ebola is that pregnant women were left out of clinical trials of the vaccines. Since Ebola is so deadly, there were excess deaths because pregnant women were not given the same opportunity to be vaccinated. The pandemic influenza [involving the H1N1 virus in 2009] was very similar to what we’re seeing now in that pregnant women were at an increased risk for severe disease—even more so than with COVID-19. When the H1N1 variant emerged, nobody had immunity. Before there was a vaccine available, a lot of pregnant women died in the U.S. and Australia.
What else are you seeing in the clinic?
I’ve spent months now taking care of COVID-positive pregnant women. We started testing at our institution relatively early on. We have seen everything from very mild disease in pregnant women to severely ill pregnant women with COVID-19.
What kinds of things are you seeing that made you so concerned?
Two things come to mind. Number one, we’re identifying a lot of women who are asymptomatic, who are coming in with COVID-19 and have no idea they’re infected. Women will say, “I don’t understand. I’m at home all day with my one-year-old son, we don’t go out anywhere.” In some cases, she may have even quit her job to stay at home “because I didn’t want to get COVID.” Then I’ll ask, “Who else is at home with you?” And she’ll say, “Oh, well, my husband. He has to work. I mean somebody in the family has to be bringing in the money, and so he’s a worker in a poultry farm.”
Then all of a sudden, the light bulb goes off: that it’s really hard for pregnant women to stay safe and to avoid getting COVID-19. In some cases, the disease is mild and they’re asymptomatic; in some cases, it starts out mild and becomes severe; and in some cases, we see pregnant women with COVID who are very ill.
What impact has that had on their babies that you’ve seen?
In general the impact of COVID-19 is more severe in the mothers, and they luckily tend to do well. That’s different than a disease like Zika, where usually the illness is mild in the pregnant woman but can be very severe and causes congenital defects in the baby. We are not seeing the pattern of congenital defects in babies for COVID-positive mothers. In fact, in both the literature and my experience, the babies tend to do fairly well.
Why do you think they’re protected?
It’s not easy to transmit COVID-19 from the mother to the baby. It’s not one of those pathogens that easily passes through the placenta and infects the baby, the way Zika does or cytomegalovirus. For COVID-19, the biggest risk to the baby is really after birth, both in getting COVID-19 from the mother as well as from other family members or other people who may interact with the infant. It was a big question early on whether mothers can safely breastfeed. We’re learning that, yes, they can—as long as they practice safe breast and hand hygiene and, if they’re infected, wear a mask when they’re around the baby.
What would be the incentive for not including pregnant women in the trials?
It’s harder and it’s more complicated. You really have to think through the issues. You have to collect enough information from a small group of non-pregnant persons to be confident that the vaccine, overall, is safe and that you understand how it’s working. And then, you can add in pregnant women. But it is complicated, because you have both the woman’s health to worry about as well as the developing fetus’.
The problem is that now it’s almost too late. Although some of the vaccine manufacturers are planning phase-3 placebo-controlled clinical trials with pregnant women, the problem is it’s harder and harder to enroll a woman in a trial and tell her, “hey, you have a 50 percent chance of getting the vaccine and a 50 percent chance of not getting the vaccine” when she really wants to get the vaccine and it may otherwise be available to her.
Given what we know now about COVID-19 vaccines in pregnant women, what are the remaining concerns? Are more trials necessary?
At this point, thousands of pregnant women are being vaccinated. We now need to follow those women to make sure that it worked like it does in nonpregnant persons. More important, we need to make sure that the infants born to vaccinated women are healthy.
From what you’re saying, there’s no reason to believe that they won’t be healthy.
Yes, there’s no theoretical reason why the vaccine would not be safe in pregnancy. But again, it is important that we don’t just say, “too late!” We need to actually follow these women and ensure that their outcomes are good.
What questions do you hear from pregnant women about the COVID-19 vaccines?
One question I hear often is, “I’m thinking about doing IVF [in-vitro fertilization], should I get immunized?” The answer is yes. Before you get pregnant, it’s a great time to get all your vaccinations, including COVID-19, if you are eligible.
Another question I hear is, “Does the vaccine result in sterilization? Can I become sterile if I take the vaccine?” That is a myth that has been propagated on social media, and in one blog in particular. It was supposedly based on a false claim that [one of the COVID-19 vaccines] had a protein that was similar to a placental protein. There is no truth to it, but it just keeps getting circulated.