Introduction

The Tdap vaccine is a combination vaccine that protects against three dangerous diseases: tetanus, diphtheria, and pertussis (also known as whooping cough) ⁶. Each of these illnesses can cause serious health problems and even death, especially in young babies ⁶.

Tetanus is caused by bacteria that can enter the body through cuts or wounds, producing a toxin that attacks the nervous system and causes painful muscle spasm and stiffness. If untreated, tetanus can be fatal ⁶. Diphtheria is another bacterial infection that can create a thick coating in the throat or nose, making it difficult to breathe or swallow. In severe cases, it can damage the heart and nervous system. Pertussis is a highly contagious disease that causes severe coughing fits ⁶. These coughing fits can make it hard to breathe and sometimes lead to vomiting or exhaustion. While older children and adults often recover from pertussis without long-term problems, the disease is much more dangerous for newborn babies. In some cases, it can cause pneumonia, brain damage, seizures, or even death ⁶.

Vaccines are one of the most effective ways to protect people from these diseases. Babies and young children receive the DTaP vaccine, which is similar to Tdap but made for younger age groups ¹. However, newborns cannot get their first dose of DTaP until they are about two months old. This means that for the first weeks of life, babies are very vulnerable to these illnesses, particularly pertussis ¹.

Following notable pertussis activity in parts of Canada around 2012–2013, the National Advisory Committee on Immunization (NACI) issued a formal recommendation in 2018 that Tdap be given during every pregnancy to protect infants too young to be vaccinated. NACI advised that pregnant people receive the vaccine ideally between 27 and 32 weeks of pregnancy, regardless of their previous vaccination history. Receiving the vaccine during this time gives the mother’s body a chance to produce antibodies, which are special proteins that fight off disease ¹. These antibodies pass through the placenta to the baby before birth. This process, called passive immunity, helps protect the baby for the first few months of life until they can start their own vaccines ¹.

Even though research has shown that this approach is safe and effective, not every pregnant person in Canada gets the Tdap vaccine ² ⁴. Uptake varies widely across the country. Some people worry about vaccine safety during pregnancy, others have not heard about the recommendation, and still others face access barriers because of geography or gaps in prenatal care ² ⁴. Understanding why some people get the vaccine and others do not is essential for improving vaccination rates and protecting more babies from pertussis.

To better understand this issue, I conducted a literature review to examine vaccination rates, reasons for hesitancy, and strategies to increase uptake.

Methodology

The literature review was conducted using the Ovid platform, which allows researchers to search multiple medical and scientific databases. For this review, I used Embase, MEDLINE, and APA PsycInfo. I also reviewed Canadian government reports and public health documents to understand official recommendations and vaccination trends.

The search used specific keywords including “pregnancy,” “gestation,” “Tdap,” “DTaP,” “maternal immunization,” and “Canada.” I only included studies conducted in Canada, involving pregnant people, and focusing on Tdap or DTaP vaccination. Studies from other countries or not about pregnancy were excluded.

After applying these criteria, I identified six directly relevant articles. These studies provided information about vaccination rates, determinants of uptake, and potential solutions.

Discussion

Research shows that receiving the Tdap vaccine during pregnancy is one of the best ways to protect newborns from whooping cough. The antibodies produced after vaccination pass to the baby and protect them until they can begin their own vaccine series. Multiple studies estimate high protection in early infancy—often around 80–90 % in the first two months of life, though estimates vary by design and setting ² ⁴. Importantly, Canadian and international studies have found no evidence that the vaccine harms the baby or the mother ⁶.

Despite this, vaccination rates have not always been high. In Ontario, in the period soon after the 2018 NACI recommendation, only about one in four pregnancies included a Tdap dose ¹. National coverage has improved since then. According to the Statistics Canada 2021 Survey on Vaccination during Pregnancy, coverage increased from 44 % in 2019 to 65 % in 2021 ¹. Rates vary significantly between provinces: approximately 80 % in Atlantic Canada (e.g., Nova Scotia 80.4 %) compared with 52.4 % in British Columbia ¹. These differences may reflect when each province implemented its program and how strongly they promoted it to providers and the public.

One of the clearest patterns is the impact of a healthcare provider’s recommendation. In 2021, 86 % of pregnant people who received a recommendation were vaccinated, compared to only 9 % who did not ¹. However, provider recommendation rates were historically low. In 2019, only 49 % of pregnant people reported being advised to get the vaccine; this rose to 69 % in 2021 ¹.

Surveys of maternity care providers before 2018 found substantial variation by profession in confidence, scope of practice, and logistics. Only about 35 % reported routinely recommending Tdap during pregnancy, and many cited practical barriers rather than opposition ⁵. For example, some midwives expressed more concern about safety, and some pharmacists believed other providers should take the lead ⁵.

Vaccine hesitancy can often be overcome with clear, trusted communication. Many pregnant people who were initially hesitant accepted the vaccine after receiving reassurance from their provider ² ⁴ ⁵. Offering the vaccine during regular prenatal appointments improves uptake, while failing to mention it often results in missed opportunities ⁵. Common reasons for refusal include lack of awareness, underestimating the seriousness of pertussis, concerns about side effects, and difficulties accessing vaccination services ⁵. Certain groups—including younger mothers, those in rural areas, and lower-income families—are less likely to be vaccinated, mirroring patterns seen with influenza vaccination during pregnancy ⁵.

Research suggests several strategies to improve vaccination rates:

  • Make Tdap vaccination a routine part of prenatal care.
  • Provide training for all maternity care providers—including midwives and pharmacists—to increase confidence in recommending and administering the vaccine ² ⁴ ⁵.
  • Strengthen public communication with clear, culturally appropriate messaging.
  • Target outreach to communities with lower uptake and ensure vaccine availability in all maternity clinics ² ⁴ ⁵.

The COVID-19 pandemic may also have affected Tdap vaccination rates ³. Some people were less willing to attend in-person medical appointments during public health restrictions, and healthcare systems were focused on COVID-19 vaccine delivery, which may have reduced attention to other immunizations ³. Ongoing research will help determine the long-term impact.

Conclusion

The Tdap vaccine during pregnancy is a safe and effective way to protect newborns from a potentially deadly disease. Canada has made important progress in increasing coverage, especially after the vaccine became publicly funded in most provinces, but further efforts are needed. Provider recommendation remains the single most powerful factor influencing uptake.

By combining strong public health messaging, provider training, expanded scope of practice, and targeted outreach to underserved groups, Canada can further increase Tdap vaccination rates. These steps will not only protect infants from pertussis but also strengthen maternal immunization for other recommended vaccines, such as influenza and COVID-19, improving health outcomes for mothers and babies nationwide.

References

  1. Results of the Survey on Vaccination during Pregnancy 2021. (2022, December 13). [Research]. Government of Canada. https://www.canada.ca/en/public-health/services/publications/vaccines-immunization/survey-vaccination-during-pregnancy-2021.html
  2. Dubé, E., Trottier, M.-E., Vivion, M., Ouakki, M., Brousseau, N., Guay, M., Laghdir, Z., Boucoiran, I., Tapiéro, B., & Quach, C. (2022). Do intentions lead to action? Results of a longitudinal study assessing determinants of Tdap vaccine uptake during pregnancy in Quebec, Canada. BMC Pregnancy and Childbirth, 22, 477. https://doi.org/10.1186/s12884-022-04809-6
  3. Greyson, D., Correia, R., Howard, M., Darling, E. K., Kirkwood, D., Davis, A., Mniszak, C., Jones, A., Molinaro, M., & Vanstone, M. (2024). SARS-CoV-2, Tdap, and influenza vaccination during pregnancy from 2019 to 2022 in Ontario, Canada: A population-based retrospective cohort study. CMAJ: Canadian Medical Association Journal, 196(32), E1100–E1113. https://doi.org/10.1503/cmaj.231522
  4. Li, Y., Brousseau, N., Guay, M., Dubé, È., Laghdir, Z., Boucoiran, I., Tapiéro, B., & Quach, C. (2022). Coverage for pertussis vaccination during pregnancy with 4 models of vaccine delivery: A quasiexperimental, multicentre observational study. CMAJ Open, 10(1), E56–E63. https://doi.org/10.9778/cmajo.20210011
  5. MacDougall, D. M., Halperin, B. A., Langley, J. M., McNeil, S. A., MacKinnon-Cameron, D., Li, L., & Halperin, S. A. (2016). Knowledge, attitudes, beliefs, and behaviors of pregnant women approached to participate in a Tdap maternal immunization randomized, controlled trial. Human Vaccines & Immunotherapeutics, 12(4), 879–885. https://doi.org/10.1080/21645515.2015.1130193
  6. Antoniou, T., McCormack, D., Fell, D. B., Kwong, J. C., & Gomes, T. (2023). Impact of national recommendations for routine pertussis vaccination during pregnancy on infant pertussis in Ontario, Canada: A population-based time-series study. BMC Pregnancy and Childbirth, 23, 627. https://doi.org/10.1186/s12884-023-05938-2

By Farhana Bhanji