Vaccines. Thanks to the COVID-19 pandemic, most people have strong opinions on vaccines today. During pregnancy, there are always a lot of questions about vaccines.
You can get vaccines during pregnancy.
Some vaccines, are only recommended DURING your pregnancy, while other vaccines can also be given prior to the pregnancy or postpartum.
This post is going to cover the history and basics of vaccines during pregnancy, as well as some frequently asked questions that I get about vaccines in the clinic. I’ve included a lot on getting vaccinated during the preconception period too (this is the period before you become pregnant or the period between pregnancies).
Let’s dive in.
First, A Vaccine History Lesson
The idea of a vaccine was discovered by Edward Jenner in the 18th century. Jenner noticed that milkmaids recovered from cowpox infections were immune to smallpox. Jenner used a cowpox sore from a milkmaid to inoculate a boy, who became immune to smallpox, and viola, the first documented vaccine was born (Mackin & Walker, 2021).
What vaccines are recommended in pregnancy?
Three vaccines are recommended in pregnancy for most people:
1. The Flu Vaccine
The flu vaccine wasn’t developed until the 1930s. Initially tested in the military, the effect against influenza was notable, and the vaccine was recommended for the general population. Research showed that pregnant women were more likely to have severe outcomes if infected with influenza. In 1960, health authorities recommended the flu vaccine to all pregnant women even though studies were lacking to support the recommendation (Mackin & Walker, 2021).
The Centers for Disease Control and Prevention didn’t support the flu vaccine recommendation for pregnant women until 1997 and only in 2009 did the United Kingdom and Australia include the flu vaccine in their recommendations for pregnancy care (Mackin & Walker, 2021).
It wasn’t until 2005, that a randomized controlled trial was completed with pregnant women and the flu vaccine or the pneumonococcal vaccine. Called The Mother’s Gift Project, the study found:
- Pregnant women who received the flu vaccine were 36% less likely to have a respiratory illness with fever than those women who received the pneumococcal vaccine.
- Infants of vaccinated pregnant women were 63% less likely to have influenza (Mackin & Walker, 2021).
Another randomized controlled trial in Nepal noted similar findings in 2011 (Mackin & Walker, 2021).
2. The TDaP Vaccine
The TDaP vaccine is given to pregnant women to reduce the chance of their newborn baby having pertussis. Pertussis is a bacteria that is highly contagious and causes the most deaths in infant that are 2 months of age or less. Infants less than 2 months of age are usually only vaccinated against hepatitis B.
The TDaP vaccine recommendation for pregnant and postpartum people is relatively new even though the vaccination against pertussis started in the 1930s. In 2006, the ACIP (Advisory Committee on Immunization Practice) recommended TDaP vaccination to postpartum people; the committee noted that pregnant women could receive the vaccination too, but the focus of the recommendation was the postpartum population. In 2010, California had a pertussis outbreak and subsequent infant deaths from pertussis. The state recommended vaccination of pregnant women to reduce the spread of pertussis and to protect young infants. In 2011, the ACIP published the same recommendation for women that were not previously vaccinated. Then, in 2012, the ACIP updated the recommendation to include all pregnant women, for every pregnancy, between 27 to 36 weeks of pregnancy, regardless of prior vaccination status. When the recommendations were made, the was little evidence to support safety of given pregnant women TDaP. Since that time multiple studies have compared TDaP vaccination between women vaccinated in pregnancy and those who do not vaccinate and have found the vaccine to be safe, not associated with increased adverse outcomes for mother or baby (Moro et al., 2015).
The United Kingdom followed suit after a pertussis outbreak in 2012. Originally, the United Kingdom recommended the vaccine during 28 to 38 weeks of pregnancy, but in 2016, they amended the recommendation from 16 to 32 weeks of pregnancy to offer more protection to preterm infants (Mackin & Walker, 2012).
3. The COVID-19 Vaccine or Boosters
The COVID-19 vaccines and boosters are recommended for pregnant or postpartum people to prevent risks associated with COVID-19 during pregnancy. There are a number of risks associated with COVD-19 infection to the mother and the baby. mRNA vaccines are preferred over the John & Johnson vaccine. Vaccination can occur in any trimester and the recommendation is the sooner in the pregnancy the better to offer the mother the most reduced risk from th evirus. the COVID-19 vaccine can be administered with other vaccines, such as flu or TDaP (ACOG, 2022).
And the Society for Maternal-Fetal Medicine maintains a resource page here with videos, education and infographics in English and Spanish.
This video also offers an overview about the COVID-19 vaccine and pregnancy:
For some people, there is a fourth vaccine.
If you have Rh-negative blood type, a fourth vaccine called Rhogam is also recommended during your pregnancy. (If you’re not sure what your blood type is, it should have been tested with your first set of prenatal labs. Most people have Rh positive blood.)
When are the vaccines recommended during my pregnancy?
The flu vaccine is recommended at the start of flu season each year for each pregnant person, or any time during flu season. Flu season runs October 1st – April 1st but can start earlier or later during the year. People can also get infected with the flu when it is not flu season.
The COVID-19 boosters are recommended anytime during pregnancy.
The TDaP vaccine is recommended between 27-36 weeks of pregnancy, but can be given any time during pregnancy, for example, if you step on a rusted nail while pregnant at 20 weeks and haven’t had a tetanus booster in 10 years. The urgent care is probably going to recommend a booster at that time.
Rhogam is recommended at 28 weeks of pregnancy. The vaccine antibodies only last about 12 weeks which is why the timing is 28 weeks.
None of these vaccines are live vaccines.
What percentage of women get the flu vaccine during pregnancy?
In the United States, about 50% of women choose to get the flu vaccine while pregnant (Mackin & Walker, 2021).
What percentage of women get the TDaP vaccine during pregnancy?
In 2021, about 53% of women reported getting the TDaP vaccine during pregnancy (Centers for Disease Control and Prevention [CDC], 2021).
My provider told me I don’t have immunity to rubella or varicella, but they also told me I can’t get these vaccines while pregnant. Why are the varicella and rubella vaccines recommended postpartum and not during pregnancy?
Great question. The MMR (measles, mumps, rubella) and Varicella vaccines are live vaccines. This means the live virus could cause an active infection in the baby if the virus crossed the placenta. This is a theoretical concern (i.e. our best science tells us this is possible) but there’s not evidence to support it. And it’s unlikely any research team is going to test out live vaccines on pregnant women in any trial.
To really understand the diseases and recommendations, you need a little more information. Let’s start with rubella.
In the 1940s, an Australian eye doctor noted that women infected with rubella in early pregnancy had more infants with congenital cataracts. Over the next 20 years, a list of birth defects from congenital rubella syndrome was assembled.
These defects include:
- Heart defects
- Intellectual disabilities
- Liver/spleen damage
- Low birth weight
- Skin rashes on the baby at birth (CDC, 2020a)
There is not a cure for a lot of these syndrome components.
Then, the rubella vaccine was created in 1969. Less than 10 people are reported to have rubella in the United States annually and all rubella infections since 2012 were from exposure to the virus while individuals were living or traveling outside the United States (CDC, 2020b). Between 2005-2018, 15 babies with congenital rubella syndrome were reported in the United States (CDC, 2020a). Although rubella is rare in the United States, it is still endemic in other parts of the world (CDC, 2020b).
In addition to the defects listed above, rubella infection in pregnancy can cause miscarriage and fetal death. If rubella infection occurs during the first 12 weeks of gestation or between 13-16 weeks of gestation, risk of congenital defect in the fetus is 85% and 50%, respectively (AAP & ACOG, 2017).
Because of these known risks, women should be educated to prevent pregnancy for 3 months after the MMR vaccine is received.
But what if I got a MMR booster and then found out I was pregnant? Good question. There’s actually some data on women who received the MMR vaccine before they knew they were pregnant. From 1971 to 1989, 1,221 pregnant women that received the MMR vaccine while pregnant or before they knew they were pregnant were enrolled in in a registry by the CDC called Vaccine in Pregnancy. There were NO cases of fetal abnormalities in these women and the registry was closed; this finding has been confirmed by other studies (Bozzo, Narducci, & Einarson, 2011).
Onto varicella, or the chickenpox.
Chickenpox is uncommon today because many older adults have had the virus and are immune, while many younger adults or children receive the vaccination. Because of this, rates of chickenpox in the community are low.
If a pregnant person gets chickenpox while pregnant, there are risks to the both the pregnant person and the baby. Chickenpox is spread by air droplets, secretions of someone with chickenpox or touching someone that has a chickenpox rash. People with shingles can also spread the chickenpox virus to someone who does not have immunity to chickenpox (March of Dimes, 2021).
The biggest risk to the mother if she gets chickenpox while pregnant is developing pneumonia – a significant lung infection that occurs in 10-20% of pregnant women that get the chickenpox (March of Dimes, 2021)..
The risks to the baby depend on when you get the chickenpox during your pregnancy.
Risks before 20 weeks are rare but include scars on the baby’s skin, problems with arms, legs, brain or eyes, stomach/intestinal problems and low birth weight (March of Dimes, 2021).
If you get the chickenpox between 2 weeks prior to birth to 2 weeks after birth, you can still infect the baby with the virus, but the infection is more mild.
But if you get the chickenpox right before birth or after birth (5 days before the birth to 2 days after birth) the baby is at risk to get neonatal varicella.
Because of the risks from varicella and rubella to pregnant persons and babies, pregnant persons are tested for their immunity status at the beginning of every pregnancy.
If I can’t get a vaccine to prevent rubella or varicella in pregnancy, how do I protect myself and my baby?
Both varicella and rubella are very contagious, therefore, avoidance of anyone with known disease or symptoms of sickness is recommended through your entire pregnancy.
This includes elderly people with active shingles outbreaks that may be in your inner circles of friends or family.
What if I received two MMR boosters but my immune status/blood work is showing up as non-immune?
You may not need a booster but should review your record with your provider.
Adults with written documentation of one or two MMR vaccines may not need an additional booster based on the following CDC recommendation:
It’s important to note that there is an exception to the first statement in the fine print. When there is a mumps outbreak, the CDC recommends a booster.
When should a provider review your vaccine record?
Ideally, before you become or plan to become pregnant. Otherwise, your immunization record should be reviewed at your first pregnancy visit.
When is the best time to catch up on my vaccines?
Back in 2019, I did a great post on the preconception visit. Preconception care is care you receive PRIOR to becoming pregnant that helps you and the baby to have the healthiest pregnancy possible. Read the post for a full recap on all the components of preconception care or check out the preconception tool for free (don’t forget to click on anything underlined on the tool – those are active hyperlinks that take you to TONS of other sources for education).
The following vaccines should be reviewed in a person’s immunization history before they plan to become pregnant:
- DTaP (diphtheria-tetanus-pertussis): There is a moderate recommendation to include a review of DTaP vaccination history in preconception assessments but evidence is based on expert opinion/case studies. The vaccine is recommended for a two-fold reason: one, experts think that the vaccine can protect the baby from neonatal tetanus through passive immunity, and two, when received by the mother postpartum, the vaccines helps to prevent pertussis in the newborn/infant (Jack et al., 2008).
- HPV (human papillomavirus) vaccine: There is a moderate recommendation that the HPV vaccine should be included in preconception assessments and evidence is from at least one randomized controlled trial possibly done before pregnancy. Women should be screened per ASCCP guidelines for cervix abnormalities from the HPV virus. The group proposes that the HPV vaccination could prevent procedures to the cervix during pregnancy that may be indicated from abnormalities caused by the HPV virus (Jack et al., 2008).
- Hepatitis B: There is a strong recommendation that the Hepatitis B vaccine should be included in preconception assessments but evidence is from expert opinion/case studies. The recommendation is for all high risk women to be vaccinated before pregnancy (Jack et al., 2008).
- MMR (measles, mumps, rubella): There is a strong recommendation that the MMR vaccine should be included in preconception assessments and evidence is from time series with or without intervention. The supplement recommends screening all women for rubella immunity and to vaccinate women without immunity prior to becoming pregnant. The group recommends women avoid pregnancy for 3 months after MMR vaccination (Jack et al., 2008).
- Influenza: There is insufficient evidence to include or exclude the recommendation to include the influenza vaccine in preconception assessments and evidence is from expert opinion/case studies. Influenza vaccination is recommended for all pregnant women, especially those considered high risk for influenza complications (Jack et al., 2008).
- Varicella: There is a moderate recommendation that the varicella vaccine be included in preconception assessments and evidence is from expert opinion/case studies. Since the varicella vaccine is contraindicated (not recommended) in pregnancy, screening for varicella immunity or a history of the disease is recommended in a preconception assessment. The recommendation is for all women without evidence of varicella immunity to receive the vaccine prior to becoming pregnant (Jack et al., 2008).
Can I decline vaccines during pregnancy?
Yes. You can always decline an intervention. Be sure you understand the alternatives, risks and benefits of the intervention in the setting of your own medical problems and health status, and why you declining it.
Can I decline vaccines after birth?
Yes. Even if a vaccine is ordered by a provider or is a standing protocol on a unit, you still have to give permission for a healthcare member to administer the vaccine to you.
However, most vaccine antibodies are shared through breastmilk and offer a benefit to the baby while you are breastfeeding.
Which vaccines are not recommended in pregnancy?
Live vaccines, such as MMR and chickenpox/varicella, and the live influenza vaccines are not recommended in pregnancy (ACOG, 2018).
The HPV vaccine is also not recommended in pregnancy but women who have received the vaccine without knowing they are pregnant have not reported adverse outcomes to date (AAP & ACOG, 2017).
A great table about which vaccines are recommended, contraindicated, have no recommendation or need to be decided on a case by case basis is here.
Can’t my provider look up my vaccine records?
Maybe. It depends on where you got your vaccines and how your state maintains vaccine records. For example, in Virginia, we can generally see most childhood vaccine records if people went to the same place or provider in most electronic health records. For this to work, the systems have to talk to one another.
If you’ve had vaccines all over the country or the world, it is less likely that providers will be able to see your electronic vaccine record.
What if I don’t have my vaccine record?
That’s okay in almost every circumstance.
One, there are some boosters that are recommended annually or on a regular basis and don’t require a vaccine record.
What if I don’t remember what vaccines I got in the hospital after my last birth?
This is common. Especially if you’ve had a couple of babies over a couple of years and while you were on the postpartum unit, you remember getting some vaccines.
This is also okay. And understandable. If you have had your babies at the same hospital, the hospital should be able to see what vaccines you were given during your previous stay. Simply ask the nurse to print you a vaccine record prior to discharge for your records.
If you are having your baby at a different hospital, you can request your medical records from your prior hospital. Any vaccines given should be in your records.
How do I request a vaccine record? Where should I keep my vaccine record?
Contact the medical records department of the hospital, hospital system or clinic where you received care. Try to be specific about what you are requesting.
Example: Inpatient records from childbirth 10/1/21-10/3/21.
Every patient has a right to their medical records but you have to fill out a release of paperwork to get the records.
Can I get multiple vaccines at the same time?
Yes. This can happen during pregnancy or postpartum.
Pregnancy example: You are 27 weeks pregnant and it’s flu season. You also have Rh-negative blood. At your 28 week visit, you may be offered three vaccines (flu, TDaP and Rhogam).
Is anyone tracking adverse outcomes from vaccines given in pregnancy?
The groups of people that receive a vaccine during a recommended time or outside a recommended time are collected on a registry. Most registries are easy to find online and offer more information about the studies done on the vaccine and the types of people that were in the study (i.e. pregnant or not pregnant). The FDA maintains a list here.
For the COVID-19 Vaccines, there is a registry called the V-safe Pregnancy Registry. Pregnant women that choose to get the COVID vaccine during pregnancy are encouraged to enroll. Read about the registry here.
What infographics are available about vaccines and pregnancy?
Line ’em up…here we go!
COVID-19 Vaccines: Infographic (Johns Hopkins)
COVID-19 Vaccination in Pregnancy (British Society for Immunology)
Talking to Pregnant Women About Vaccines (CDC, 2019)
Vaccinations and Pregnancy (March of Dimes)
What other handouts do you recommend about vaccines and pregnancy?
That’s a wrap! Hope you found the history, education and FAQs helpful. I’ll be sure to update the information as it changes.
American Academy of Pediatrics, & American College of Obstetricians and Gynecologists. (2017). Guidelines for perinatal care (8th ed.). doi: 10.1002/14651858.CD003519.pub3
American College of Obstetricians & Gynecologists. (2018). Maternal immunization. https://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2018/06/maternal-immunization
American College of Obstetricians & Gynecologists. (2022). COVID-19 vaccines and pregnancy: Key recommendations and messaging for clinicians. https://www.acog.org/-/media/project/acog/acogorg/files/pdfs/clinical-guidance/practice-advisory/covid19vaccine-conversationguide-121520-v2.pdf?la=en&hash=439FFEC1991B7DD3925352A5308C7C42
Bozzo, P., Narducci, A., & Einarson, A. (2011). Vaccination during pregnancy. Canadian Family Physician,57(5), 555-557. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3093587/#:~:text=Live%20vaccines%20during%20pregnancy,vaccines%2C%20are%20contraindicated%20during%20pregnancy.
Centers for Disease Control and Prevention. (2020a). Pregnancy and rubella. https://www.cdc.gov/rubella/pregnancy.html#:~:text=Pregnant%20women%20who%20contract%20rubella,Deafness
Centers for Disease Control & Prevention. (2020b). Rubella (German measles, three-day measles). https://www.cdc.gov/rubella/about/in-the-us.html
Centers for Disease Control & Prevention. (2021). Flu and tdap vaccination coverage among pregnant women – United States, april 2021. https://www.cdc.gov/flu/fluvaxview/pregnant-women-apr2021.htm
Jack, B., Atrash, H., Coonrod, D., Moos, M.K., O’Donnell, J., & Johnson, K. (2008). The clinical content of preconception care: An overview and preparation of this supplement. American Journal of Obstetrics & Gynecology, 199(6), S266-S279. https://www.ajog.org/article/s0002-9378(08)00887-9/fulltext#tbl1
Mackin, D., & Walker, S. (2012). The historical aspects of vaccination in pregnancy. Best Practice & Research. Clinical Obstetrics & Gynaecology, 76, 13-22. doi: 10.1016/j.bpobgyn.2020.09.005
March of Dimes. (2021). Chickenpox during pregnancy. https://www.marchofdimes.org/find-support/topics/pregnancy/chickenpox-during-pregnancy
Moro, P., McNeil, M., Sukumaran, L., & Broder, K. (2015). The centers for disease control. andprevention’s public health response to monitoring tdap safety in pregnant women in the United State. Human Vaccines & Immunotherapeutics, 11(12): 2872-2879. doi: 10.1080/21645515.2015.1072664