Can you guess the leading cause of infant hospitalizations in the United States? You might think accidents, allergic reactions, or the flu, but the answer is actually respiratory syncytial virus (RSV). Every year, RSV sends 58,000 to 80,000 children under the age of 5 to the hospital.

Having a baby in the fall or winter has always meant that parents need to be extra careful about RSV. Fortunately, in 2023 two new ways to protect infants against this virus became available: a vaccine given to women between 32 and 36 weeks of pregnancy and an antibody (passive immunization) that is given directly to babies after birth. Today, we’re covering some of the most common questions we get at MotherToBaby about RSV prevention.

Q: What is the maternal RSV vaccine? When is it given?

The maternal RSV vaccine (brand name Abrysvo^®) is a protein subunit vaccine (it contains proteins the body needs to make antibodies against RSV). The vaccine does not contain live virus that can cause RSV. When a woman gets the RSV vaccine during pregnancy, the antibodies she makes can also pass to the developing fetus. These antibodies can help protect the baby from RSV during the first 6 months of life.

The Abrysvo^® RSV vaccine can be given to women who are 32 to 36 weeks pregnant who have not received a maternal RSV vaccine in a previous pregnancy. The RSV vaccine is only recommended for use during pregnancy between September and January in most of the United States. 

Q. What is an infant RSV antibody? When is it given?

Infant antibodies, also called passive immunizations, are another effective way to help protect babies from RSV. Two RSV antibodies are currently available: nirsevimab (Beyfortus®) and clesrovimab (Enflonsia®). The RSV antibody is recommended for infants younger than 8 months who are entering their first RSV season if their mothers did not receive the maternal RSV vaccine during pregnancy. Infants and children ages 8 to 19 months who are at high risk for severe RSV illness and entering their second RSV season may also be eligible for the antibody. The RSV antibody is available between October and March for most of the United States and starts working immediately after it is given.

For more information about timing, eligibility, and benefits of infant RSV antibodies, talk with your child’s pediatrician.

Q: Is one of these options better than the other?

Patients can choose either the maternal vaccine or the infant antibody. Both are great options for protecting infants against RSV, and there is currently no preference for one over the other. A slight benefit of getting the RSV vaccine during pregnancy is that most babies will be born with immediate protection if the vaccine is given at least 2 weeks before delivery. Some parents might also prefer the maternal vaccine because it avoids an extra injection (shot) for the baby.

Q. How do we know the RSV vaccine is ok to get in pregnancy?

Studies on the Abrysvo^® RSV vaccine have not found a higher chance of birth defects. It’s also reassuring to note that the vaccine is given in the third trimester (between 32 and 36 weeks), which is past the critical period when most birth defects could happen.

Early clinical trials on the vaccine observed slightly more preterm births in women who received the Abrysvo^® RSV vaccine than in those who did not (5.7% in the vaccinated group vs. 4.7% in the placebo group). However, newer data from larger studies has not found a higher chance of preterm birth following RSV vaccination in pregnancy. Check out the MotherToBaby RSV vaccine fact sheet for more information on this topic.

Q. If I got an RSV vaccine in my last pregnancy, do I need to get it again in my next pregnancy?

The simple answer is no. At this time, the maternal RSV vaccine is only recommended for women who have not gotten it in a previous pregnancy. Researchers need time to determine if getting the vaccine once can provide ongoing protection for future pregnancies, or if a booster dose is needed in every pregnancy.

If you received the RSV vaccine during a previous pregnancy and are pregnant again, your baby can get an infant RSV antibody to help ensure they are protected.

Making Your Choice

No matter whether you decide on the maternal RSV vaccine or an infant RSV antibody, you’re making a great choice to protect your baby from RSV! Still have questions? Remember that MotherToBaby can be reached by chat, text, phone, or email with questions about the RSV vaccine or any other exposure in pregnancy or while breastfeeding.

Emily called MotherToBaby and confided, “My husband and I are thinking about getting pregnant…I am so excited but scared, too. I am wondering what I can do to make it more likely we will have a healthy pregnancy and baby.”   

I assured Emily that we love it when people call ahead of their pregnancy and ask these questions. Preconception health is a topic that does not receive as much attention as it deserves, and it is important for both Emily and her husband. Good preconception health care can impact fertility and make it easier to conceive, and also helps to improve pregnancy outcomes and the health of the baby.   

Here is a preconception prep guide– because if you are ready to have a baby, you want to take steps now to keep you and your baby as healthy as possible:

• Make a pre-conception checkup appointment: Begin by making an appointment about three months in advance with your obstetrical care provider. At that appointment you can confirm you are in good health. If you have any chronic conditions such as high blood pressure, thyroid disease, depression or diabetes you and your provider can make sure the condition is being managed effectively and confirm that any prescription or over-the-counter medications you are taking can be continued in the pregnancy. If you have a question about medications during pregnancy, MotherToBaby can help by providing you with information to bring to your appointment.
• Begin taking a prenatal vitamin: If you are not already taking a vitamin with folic acid this is a great time to start. The Centers for Disease Control and Prevention (CDC) recommend that all women who can become pregnant take a vitamin containing 400 micrograms of folic acid; this helps reduce the chances for certain birth defects such as spina bifida (when the spinal cord does not form properly).
• Review your vaccine status: During your preconception checkup, make sure that you are up to date on vaccinations such as the MMR (measles, mumps, rubella), Tdap (tetanus, diphtheria, whooping cough), influenza, and COVID. Planning ahead makes it more likely you will not get ill during pregnancy and helps protect the baby from getting infections from parents after birth.
• Get your body fit for pregnancy: Get regular exercise and consider whether you and your partner are at your preferred weight. If not, make plans to remedy that prior to attempting to get pregnant. You can also learn more about a healthy diet and nutrition. This is something that may improve fertility in both parents and lay the groundwork for a healthy pregnancy.
• Eliminate harmful exposures: It goes without saying that this is a great time to make lifestyle changes such as reducing use of alcohol, tobacco, and recreational drugs.  Addressing stress and mental health concerns up front can improve fertility, make the whole pregnancy experience better, and prepare you for the excitement and hard work of parenthood.
• Evaluate your home and work environment: If you and your partner are exposed to toxic substances like lead in your work or home environment, working to reduce those exposures is very effective when done ahead of the pregnancy.

MotherToBaby has many resources for Emily and her husband – and you!  We have fact sheets on medications, herbal agents and supplements, diabetes and other health conditions, illnesses and vaccinations, occupations such as veterinarian and dental, exercise, paternal exposures, and cosmetics (sunscreen, skin creams, nail polish, hair dye). There are also useful blogs and podcasts, and whole web pages on various conditions, and if you have questions, our information specialists are here to help.

You may have heard that the Centers for Disease Control and Prevention (CDC) recently recommended a new vaccine for use in the third trimester of pregnancy. Known as Abrysvo^TM, the vaccine helps protect newborns against severe cases of respiratory syncytial virus (RSV). RSV is the leading cause of infant hospitalization in the United States, with anywhere from 58,000-80,000 hospitalizations occurring each year among children younger than 5. Even more upsetting is that 100-300 children under age 5 die from RSV every year. With these statistics in mind, this new RSV vaccine is exciting news for infants and their families.

Ava, 24 weeks along with her first pregnancy, contacted the MotherToBaby live chat service early one morning with some questions about the new RSV vaccine. First, she wanted to understand how vaccinating a pregnant woman could provide protection for a baby. As a Teratogen Information Specialist, I was happy to answer this question for Ava. I started by explaining that when a person gets vaccinated, their body makes antibodies. These antibodies protect the body against the actual infection if a person is exposed to the virus or bacteria later in life. During pregnancy, the antibodies that a pregnant woman makes after being vaccinated can cross the placenta and pass to the developing baby, providing the newborn with some protection against the infection during the first few months of life.

I went on to explain that although the RSV vaccine is new, the idea of getting a vaccine during pregnancy to protect the baby (called “passive immunity”) has been around for some time. The Tdap vaccine, which protects against tetanus, diphtheria, and pertussis (whooping cough), has been recommended for use in pregnancy since 2011. Whooping cough is another infection that can be very serious for newborns, so having protection from birth as a result of maternal vaccination is ideal. The flu shot and COVID-19 vaccine can also pass antibodies to the developing baby during pregnancy. This is great news since newborns can’t get their own flu or COVID-19 shots until 6 months of age and need to rely on passive immunity in the meantime.

Next, Ava had a question about when she should get the RSV vaccine. She had plans to get her flu shot and Tdap vaccine at her next prenatal visit at 28 weeks. She wanted to know if she could get the RSV vaccine at the same time. Although these three vaccines (along with the updated COVID-19 vaccine) can all be given on the same day, the RSV vaccine should be given during a specific timeframe in order to pass as many antibodies as possible to the baby. Experts recommend that the RSV shot be given between 32 and 36 weeks of pregnancy. This allows enough time for RSV antibodies to pass to the baby before delivery.

With this recommendation in mind, Ava decided that her prenatal appointment at 32 weeks would be the perfect time to get the RSV vaccine. She had seen firsthand just how serious RSV can be when her 1-month-old niece was hospitalized with RSV last winter, so she didn’t want to take any chances with forgetting to get the RSV vaccine during her pregnancy.

Before we ended the chat, I mentioned to Ava that there is also a shot called nirsevimab (Beyfortus^TM) that can be given directly to babies under 8 months of age. Also known as a monoclonal antibody, this shot is another way to protect infants against severe RSV disease. Most babies do not need nirsevimab if their mom received the RSV vaccine during pregnancy. I suggested Ava talk with her healthcare provider about the pros and cons of both options.

Although having to remember to get another vaccine in pregnancy can feel like just one more thing a pregnant woman needs to add to their never-ending to do list, the decision to vaccinate can prevent serious complications from RSV, and possibly even save the baby’s life. Here at MotherToBaby we are happy to go over the current recommendations for vaccines in pregnancy and answer any questions that you may have. Don’t hesitate to call, chat, text, or email with any questions about the RSV vaccine or other exposures during pregnancy. You can also check out our newest fact sheet about this vaccine here https://mothertobaby.org/fact-sheets/respiratory-syncytial-virus-rsv-vaccine-abrysvo/.  

References:

Centers for Disease Control and Prevention. 2023. RSV Vaccination for Pregnant Women. Available at: https://www.cdc.gov/vaccines/vpd/rsv/public/pregnancy.html

Centers for Disease Control and Prevention. 2023. RSV Surveillance & Research. Available at: https://www.cdc.gov/rsv/research/index.html

It’s that time of year again, when the holidays invite family gatherings, and colder, shorter days make us long for sunny destinations. Yes, the winter travel season is upon us! Remember winters past when COVID-19 wasn’t around and we’d never heard of Zika? When we didn’t give much thought to health concerns related to hopping on a plane or going to busy holiday venues? Things are different now. If you’re pregnant, you might pause before booking airline tickets or RSVPing “yes” to that extended family reunion. Take a moment to consider the possible risks associated with your plans, and how you might reduce them (by taking precautions) or eliminate them (by making alternate plans instead). Here are a few things to think about:

COVID-19:

Try as we might, we can’t escape it or wish it away. We are, in fact, still in the middle of a pandemic, with new variants appearing and cases still rising and falling unpredictably in most places. Traveling on public transportation (such as airplanes, ships, trains, subways, taxis, and ride shares) can make getting and spreading COVID-19 more likely. So can being in crowded indoor spaces, especially if not everyone in those spaces is fully vaccinated against COVID-19 and/or wearing a mask. Having COVID-19 in pregnancy can increase pregnancy risks such as stillbirth and preterm delivery. So, how can you eliminate or reduce your chance of exposure to the virus?

• Avoid public transportation. If you must travel, using your own vehicle with members of your own household is the safest bet. Using drive-thrus or packing your own food to stop and eat along the way is safer than eating in crowded restaurants full of other holiday travelers.
• If you must travel on a plane or use other public transportation, wear a well-fitting mask the whole time (this is required), stay at least 6 feet away from other travelers when possible, and wash your hands/use an alcohol-based hand sanitizer frequently. Most importantly, make sure you’re fully vaccinated before you travel, including getting a booster dose when you’re eligible.
• Did I mention making sure you’re FULLY VACCINATED before travel? It’s the single best way to reduce the chance of getting very sick if you’re exposed to the virus that causes COVID-19. Pregnancy and being very sick don’t go well together, so this one is really, really important, whether you’re traveling or not. MotherToBaby has helpful resources on the COVID-19 vaccines and booster shot, and you can contact us to talk through any questions or concerns you may have about getting the vaccine.
• Even if you’re fully vaccinated, you might still consider wearing a mask indoors during holiday gatherings (and elsewhere), especially if you’re getting together with people from different households coming from different places. If everyone else at the gathering also wears a mask indoors, even better.  
• Find more tips and information about safer holiday celebrations and travel in the time of COVID at this link: https://www.cdc.gov/coronavirus/2019-ncov/daily-life-coping/holidays/celebrations.html.

Influenza (the Flu):

Flu season carries its own risks for people who are pregnant. Like COVID-19, having the flu during pregnancy increases the chance of being very sick compared to people who aren’t pregnant. Many of the same precautions that apply to COVID-19 apply to the flu as well:

• Get the flu shot. Like the COVID-19 vaccine, the flu shot can be given at any time during pregnancy, and can even be given at the same time as a COVID vaccine or booster. The sooner you’re vaccinated, the sooner you and your pregnancy will have good protection against becoming very sick from the flu. And (bonus!) getting vaccinated in pregnancy may pass some protective antibodies to your developing baby.
• Avoiding public transportation and crowded indoor spaces will also reduce your chance of exposure to the flu virus. Washing your hands frequently/using an alcohol-based hand sanitizer is also an excellent flu prevention technique.

Zika:

Yes, Zika is still around. There are no known “outbreaks” of Zika anywhere in the world at this time, but there is ongoing, low-level, sporadic transmission in some places. Having Zika during pregnancy increases the chance of serious and lifelong effects for a developing baby. There is no vaccine against the Zika virus.

• The safest course in pregnancy (or if you’re trying to conceive) is to avoid travel to places with a chance of exposure. Unfortunately, it’s virtually impossible now to know the exact risk of being exposed to Zika in any given country, but if you must travel, you can use the CDC’s Zika map to help you plan.
• If you travel,use insect repellent and take other precautions to help avoid mosquito bites, such as wearing long sleeves and pants. If your partner travels with you, take steps to avoid sexual transmission of Zika. If you’re planning a pregnancy, follow the recommended wait times (2 months for women, 3 months for men) before trying to conceive.

Other infections:

If you’re considering international travel, there may be other infections to consider, such as malaria and foodborne illnesses. You might also need other vaccines, so be sure to review the current vaccine recommendations for your destination. Some vaccines can be given during pregnancy, but it’s a good idea to check with your healthcare provider or contact MotherToBaby to discuss the risks and benefits of specific vaccines as you’re deciding about travel. 

Medical concerns:

Other travel considerations include the increased chance of blood clots during travel if you’re pregnant, and where you will receive medical care in case of unexpected preterm labor or another medical emergency. Before any travel, be sure to talk with your healthcare provider about any additional considerations that are specific to you and your pregnancy.

Given all these considerations, if you’re pregnant you might decide this year is a good one to enjoy low-key holidays at home and save the travel for another time. However you decide to spend the season, we hope it’s safe, healthy, and happy!

Morgan called late Friday afternoon with a question about COVID-19 booster shots. She shared that she was 37 weeks along and had received both shots of the Pfizer COVID-19 vaccine back in February, at the very beginning of her pregnancy. Morgan wanted to do what was best to protect her baby, and asked if she qualified for the booster shot that was now available.

As a Teratogen Information Specialist at MotherToBaby California, COVID-19 vaccine questions are my number one inquiry right now. With the guidance continuing to evolve as the pandemic rages on, it can be hard for pregnant women to keep up! Luckily, that’s what we are here to help with. I shared with Morgan that although the vaccines are still working well to prevent severe illness, hospitalization, and death, overall effectiveness has been shown to decrease over time (called waning immunity). Because of this decreased protection, the Centers for Disease Control and Prevention (CDC) have recommended booster shots for some people over the age of 18, including:

• Certain groups – including those who are pregnant or recently pregnant – who got both doses of an mRNA vaccine (Pfizer or Moderna) at least 6 months ago, and
• Everyone who got the Johnson & Johnson vaccine at least 2 months ago.  

So, what does this mean for my pregnant caller Morgan? Women who are pregnant and recently pregnant (up to 42 days after delivery) may be more likely to get severely ill from COVID-19. We know that there are higher risks of ICU admission, need for a ventilator, and death when a woman gets COVID-19 while pregnant, so protection of this group through vaccination is extremely important. I shared with Morgan that since it has been more than 6 months since she received her first two doses of the Pfizer vaccine, and since she is currently pregnant, she may choose to get a booster shot. The American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal Fetal Medicine (SMFM) have both recommended the booster at any time in pregnancy once you’re eligible for it.

Morgan and I went on to review the latest pregnancy data on the COVID-19 vaccines, which now includes thousands of women who have received mRNA vaccines (Pfizer or Moderna). Reassuringly, the available data does not suggest a risk for pregnancy complications (including miscarriage, preterm birth, stillbirth, effects on the baby’s growth, or infant death). Although COVID-19 booster shots have not been specifically studied in pregnancy, the Pfizer and J&J boosters are the same dose and contain the same ingredients as the initial doses, and the Moderna booster contains just half of the original dose. Most experts agree that the components of the COVID vaccines only stay in our bodies for a short time, and are not expected to cross the placenta to reach the baby.

Morgan was happy to hear that she qualified for the booster shot. Her three-year-old was in preschool, and although he wore his mask every day, she was still worried about him bringing home COVID and infecting her. She also visited her grandparents often, and wanted to keep them safe. For her, the benefits of protecting herself and her unborn baby definitely outweighed any potential risks.

Before we disconnected, Morgan asked about her sister-in-law who received the Moderna vaccine three months ago and was now pregnant. “Would she be able to get a booster?” Looking at the latest CDC guidelines, I informed Morgan that her sister-in-law would need to wait until 6 months after her second dose of Moderna before she became eligible for the booster. However, I also reminded her that her sister-in-law still has good protection against becoming very sick or hospitalized from COVID-19 from her initial vaccination. Like everyone who is pregnant, she should continue to take other precautions, such as wearing a mask and avoiding crowded indoor gatherings.

If you are unsure whether or not you qualify for a booster or you have other vaccine-related questions, please reach out to a MotherToBaby Specialist. And for anyone who has not yet received their initial COVID-19 vaccine, please know that it is strongly recommended before or during pregnancy by many organizations focused on maternal and child health, including the CDC, the American College of Obstetricians and Gynecologists, and the Society for Maternal-Fetal Medicine. If you would like to go over the latest pregnancy information for the COVID-19 vaccines, COVID-19 boosters, or any other exposures, please give us a call.