Vaccinations in pregnancy – optimising maternal and infant protection
In an era marked by rising vaccine hesitancy and resurgent infectious threats, maternal vaccination stands as a powerful safeguard for the mother and for the infant in their first six months of life. This article unpacks the latest recommendations, demystifies safety concerns and explores bold strategies to improve vaccine uptake across the preconception, pregnancy and breastfeeding continuum, providing clinicians with practical tools to champion vaccination and protect Australia’s next generation.
- Maternal vaccination protects both the pregnant woman and her infant in their first six months of life, with antibody transfer in utero and through breast milk offering vital early life protection against severe infections.
- Preconception vaccination offers a critical opportunity to address immunity gaps, particularly for rubella, varicella and hepatitis B, reducing the risk of serious congenital infections.
- Vaccines recommended during pregnancy in Australia include influenza, pertussis (diphtheria-tetanus-acellular pertussis) and, most recently, respiratory syncytial virus, with the timing optimised to maximise passive immunity for the newborn.
- Vaccination during breastfeeding is safe and beneficial, with most vaccines posing no risk to the infant and potentially enhancing passive immune protection.
- Barriers to vaccine uptake, such as misinformation, access issues and variable healthcare provider engagement, must be addressed through co-ordinated public health capacity building and communication, integrated antenatal vaccine delivery and digital health solutions.
- Future maternal vaccines, including those for group B streptococcus and cytomegalovirus, are on the horizon and sustained investment in research, surveillance and trust-building will be key to success.
Vaccination plays a crucial role in safeguarding both expectant mothers and their newborns from various vaccine preventable diseases (VPDs).1,2 By administering specific vaccines preconception, during pregnancy and while breastfeeding, immunisation confers direct protection to the pregnant woman and subsequent passive immunity to their child, thereby reducing morbidity and mortality rates among these vulnerable populations.3
For healthcare professionals, a key indispensable resource is the Australian Immunisation Handbook, the national clinical guideline for vaccination recommendations. A list of resources is provided in Box 1. Using the best scientific evidence available, the Australian Technical Advisory Group on Immunisation (ATAGI), in collaboration with other key stakeholders, develop the handbook’s recommendations for the safest and most effective use of vaccines.4 Augmenting the ongoing development of the handbook is the National Centre for Immunisation Research and Surveillance (NCIRS), with many of its collaborative works including the Sharing Knowledge About Immunisation (SKAI) and AusVaxSafety programs, providing reliable information to support healthcare professionals in discussing vaccination and VPDs with their patients.
Most, but not all, recommended vaccines are funded and delivered through the National Immunisation Program (NIP), a joint Commonwealth, State and Territory government initiative, acknowledged as one of the world’s most comprehensive immunisation programs.5-7
Recent developments, including the introduction of a new respiratory syncytial virus (RSV) vaccine into the NIP, heightened vaccine hesitancy following the coronavirus disease 2019 (COVID-19) pandemic and the resurgence of pertussis, underscore the critical need to optimise maternal vaccination uptake.8-15 Pregnant women may also be recommended to receive additional vaccines if they are at increased risk of other specific VPDs because of factors including occupation, personal behaviour or medical conditions.1 This article offers healthcare professionals an in-depth review of vaccination during preconception, pregnancy and breastfeeding, focusing on current recommendations, safety profiles, barriers to uptake and strategies to improve immunisation rates among pregnant women.
Rationale for maternal vaccination
Maternal vaccination is a crucial public health strategy designed to prevent or reduce the severity of maternal infection, fetal or congenital infection and infant infection during their first six months of life. This is achieved through a co-ordinated immunisation approach for every pregnancy. The scheduling of vaccine administration varies based on the at-risk individual (mother, fetus and/or infant), the period when the risk of infection is greatest or becomes significant, and the length of protective immunity following vaccination.16
Immunological changes in pregnancy
Pregnancy induces complex immunological adaptations that facilitate fetal tolerance while maintaining maternal immune competence.17 These adaptations include modulation of innate and adaptive immune responses, increased anti-inflammatory cytokine activity and alterations in cellular immunity.18 Although there is little robust evidence demonstrating that pregnant women are more susceptible to VPDs including influenza and COVID-19, multiple studies confirm they are at increased risk of severe complications, with higher rates of hospitalisation, intensive care unit admission and maternal mortality.19-27
Benefits of maternal vaccination
Protection of the mother
Maternal vaccination reduces the risk of severe illness, hospitalisation and adverse pregnancy outcomes.28 Strong, robust evidence demonstrates that influenza vaccination during pregnancy decreases the likelihood of influenza-related complications, including pneumonia and preterm birth.29,30
Passive immunity for the infant
One of the primary advantages of maternal immunisation is the transplacental transfer of antibodies, which provides passive immunity to the infant that is sustained during the vulnerable neonatal period.31 Immunoglobulin G is actively transported across the placenta via the neonatal Fc receptor, reaching peak concentrations in the third trimester.32 Studies have demonstrated that maternal pertussis vaccination results in a 70 to 90% reduction in pertussis cases and an up to 90.5% reduction in related hospitalisations among infants younger than three months old.33-36 Similarly, seasonal influenza vaccination during pregnancy reduces the risk of infection and related complications for mothers and their newborns.37-41
Reduction in disease burden
Widespread maternal vaccination programs have led to significant reductions in neonatal morbidity and mortality. For instance, global implementation of maternal tetanus immunisation programs has contributed to the near elimination of neonatal tetanus in many countries.42,43
Public heath impact
Maternal vaccination not only benefits individuals but also reduces the overall burden of VPDs within the broader community, as herd immunity extends to unvaccinated individuals, including premature infants and immunocompromised neonates.44,45 In Australia, sustained maternal pertussis immunisation programs have led to a decline in infant pertussis-related hospitalisations.46 Moreover, the introduction of maternal RSV vaccination is expected to further decrease RSV-related neonatal morbidity and mortality, and provide additional herd protection beyond this group, while being cost-effective.47,48
Preconception vaccination: ensuring immunity before pregnancy
Women planning pregnancy should have their vaccination history thoroughly assessed, including using the Australian Immunisation Register (AIR; available at: https://www.servicesaustralia.gov.au/australian-immunisation-register), as part of comprehensive preconception care (Box 2).1,49,50 This process is crucial to ensure optimal protection against VPDs that could result in significant pregnancy complications or congenital infections. Furthermore, given that live vaccines are generally contraindicated during pregnancy because of a theoretical risk of transmission,1,51 the preconception period provides an important opportunity for these vaccines to be administered without undue concern for adverse fetal effects.
Additionally, individuals residing in the same household should also have their vaccination status reviewed and updated to minimise the risk of transmitting VPDs to the prospective mother and the newborn.1
Managing uncertain vaccination or infection history
If a woman’s vaccination history or infection status is unclear, serological testing should be performed to verify immunity against key pathogens (Box 3).1 Should serological testing reveal insufficient immunity, the necessary vaccines should be administered, taking into consideration recommended waiting periods before conception.
Recommended preconception vaccines
Women planning pregnancy should be up to date with the following vaccines, as summarised in Table 1.1,34,52-59
Hepatitis B
Vaccination is recommended for all hepatitis B-naive women to prevent acquisition and mother-to-infant transmission.52
Measles, mumps and rubella
Infection with any of these viruses during pregnancy can have severe consequences such as congenital rubella syndrome. Women lacking confirmed immunity should receive two doses of measles, mumps and rubella (MMR) live vaccine, spaced four weeks apart, and should avoid conception for at least 28 days after the final dose.53-55
Varicella (chickenpox)
Vaccination is recommended for seronegative women to prevent congenital varicella syndrome or neonatal varicella. Two live vaccine doses should be administered four to eight weeks apart, with conception avoided for 28 days following the final dose.56
COVID-19
COVID-19 vaccination is recommended as a primary course for women who are not previously vaccinated, because of increased risk of severe disease with COVID-19 in pregnant women.1,59 Single-dose mRNA vaccines (Comirnaty JN.1 or Comirnaty Omicron XBB.1.5) are currently recommended.57
Influenza
Women planning pregnancy should receive an influenza vaccine to reduce the risk of influenza-related complications during pregnancy. Annual vaccination is recommended.30
Special risk groups considerations
Some women may require additional vaccines or vaccine schedule alterations (Box 1). This includes women who are immunocompromised because of a congenital or medical condition, or following immunosuppressive treatment, those who have previously experienced an adverse event following vaccination, and those planning overseas travel where relevant exposures are anticipated. Expert consultation may be necessary for individualised risk assessment and vaccine planning.
Vaccination during pregnancy: protecting mother and baby
Vaccination during pregnancy provides dual protection by directly safeguarding the mother against severe illness and indirectly protecting the infant via transplacental transfer of maternal antibodies.
Vaccines recommended during pregnancy
The Australian Immunisation Handbook recommended vaccines during pregnancy are detailed in the Figure.1,9,30,57,60-63
Influenza
Seasonal influenza significantly increases morbidity in pregnant women, with elevated risks of severe respiratory illness, hospitalisation, preterm labour and adverse fetal outcomes.37,64,65 Influenza vaccination is therefore strongly recommended for all pregnant women during any trimester, especially those whose pregnancy coincides with the influenza season.66 Clinical studies have consistently shown influenza vaccination during pregnancy to be safe, with no increased risk of congenital malformations or adverse maternal or fetal outcomes.1,40
Pertussis
Pertussis remains a significant public health concern, particularly for infants under six months of age who are at the highest risk for severe disease and death.67 Vaccination with reduced antigen diphtheria-tetanus-acellular pertussis vaccine (dTpa) is strongly recommended as a single dose between 20 and 32 weeks’ gestation, irrespective of previous vaccination status.1,68-71 This timing maximises the transfer of protective antibodies to the fetus, offering protection during the critical early life period. Multiple studies confirm maternal pertussis immunisation as highly effective, reducing the risk of pertussis infection in infants younger than three months by up to 90%.33-36,67 Importantly, national and international data confirm no increased risk of adverse pregnancy outcomes associated with pertussis vaccination.72-74
Respiratory syncytial virus
RSV is a leading cause of severe lower respiratory tract infection among infants, frequently resulting in hospitalisation and intensive care admission.75 Until recently, preventive options were limited; however, 2023 to 2025 marked a significant shift in RSV prevention in Australia with the approval and rollout of two complementary strategies: maternal vaccination and the monoclonal antibody nirsevimab for newborns and infants.
Maternal vaccination
The maternal RSV vaccine (Abrysvo, RSVpreF) was approved by the TGA in early 2024 and is recommended for use in pregnant women between 28 and 36 weeks’ gestation.13,76 Maternal immunisation enables transplacental transfer of RSV-specific antibodies, providing passive protection to infants during their highest risk period. Clinical trial data demonstrated robust safety profiles and high vaccine efficacy, significantly reducing infant RSV-related lower respiratory tract infections and hospitalisations.77-79
In May 2025, the TGA issued an updated warning on the known low risk of people developing Guillain–Barré syndrome following vaccination, noting, however, that the benefit–risk balance continues to remain strongly in favour of vaccination in the target groups.80 The TGA further stated they had not received any reports of Guillain–Barré syndrome following vaccination with Abrysvo as of 24 March 2025.
Nirsevimab
The TGA also approved nirsevimab (Beyfortus), a long-acting monoclonal antibody administered as a single intramuscular dose to newborns.81 Nirsevimab provides direct passive immunity and has demonstrated efficacy in reducing medically attended RSV illness and hospitalisations, including among infants with heart or lung disease, premature infants, and those under the age of two years who are immunocompromised.82-85 In April 2024, Western Australia and Queensland became the first jurisdictions to introduce universal access to nirsevimab for all newborns.86,87 As of early 2025, all Australian states and territories offer nirsevimab to all infants through either seasonal or year-round programs.88
Nirsevimab is recommended by the ATAGI for infants whose mothers did not receive RSV vaccine in pregnancy or were vaccinated less than two weeks before delivery, as well as infants at increased risk of severe RSV disease, regardless of maternal vaccination status.9
The availability of both maternal vaccination and nirsevimab raises important considerations for clinical practice. While maternal immunisation is preferred for healthy term pregnancies because of the broader benefits of protecting both mother and infant, nirsevimab offers an effective alternative or adjunct, particularly in cases of late or missed maternal vaccination, early delivery or increased infant risk. Clinicians should counsel women on both options, balancing time, infant risk and vaccine availability.
Ongoing data collection will provide important insights into the uptake and integration of these dual RSV prevention strategies. Ultimately, achieving high coverage with at least one of these options for all newborns will be crucial to reducing the national burden of RSV-related morbidity.
COVID-19
Unvaccinated pregnant women face heightened risks of severe COVID-19 associated with increased rates of hospitalisation, intensive care admission, preterm birth and stillbirth.21,27,89,90 The ATAGI recommends that only pregnant women who are unvaccinated receive a single primary dose of COVID-19 vaccine.57 Current recommended vaccines include mRNA vaccines Comirnaty JN.1 or Comirnaty Omicron XBB.1.5. COVID-19 vaccination during pregnancy has been shown to be safe and effectively induces maternal antibody transfer, offering early infant protection against severe COVID-19.91-93
Vaccines not routinely recommended during pregnancy
Most other vaccines are not routinely recommended during pregnancy unless there is a specific high-risk scenario.1 Notably, live virus vaccines such as MMR and varicella vaccines are contraindicated during pregnancy because of theoretical risks of inducing infection and subsequent complications, including adverse fetal outcomes.94 Many inactivated bacterial vaccines and inactivated viral vaccines are also not recommended during pregnancy.95,96 The Australian Immunisation Handbook makes special mention of human papillomavirus and yellow fever vaccines.97 Nonetheless, there are scenarios in which the potential benefit of vaccination during pregnancy may outweigh theoretical risks, particularly among women with significant medical or exposure risks. These cases should be individually assessed by a specialist immunisation service or healthcare provider experienced in maternal immunisation, as absolute contraindications for vaccination during pregnancy are rare.1
Vaccination during breastfeeding: ensuring ongoing protection
Breastfeeding provides essential immunological protection to infants through the transfer of maternal antibodies, particularly immunoglobulin A. Vaccination during lactation is a vital component of postpartum care, ensuring continued maternal immunity and enhancing passive immunity for the infant.
Safety of vaccination while breastfeeding
Most vaccines, including both inactivated and live-attenuated vaccines, are safe during breastfeeding.98,99 Extensive research demonstrates that vaccination during lactation does not negatively affect breast milk composition, lactation performance or infant health.100 Vaccines administered to breastfeeding women do not pose risks of vaccine-associated infections to the infant, making postpartum vaccination a practical and safe preventive health measure.92,101
Recommended vaccines for breastfeeding mothers
Breastfeeding mothers who did not receive recommended vaccines during pregnancy, especially for pertussis, should consider postpartum vaccination to ensure ongoing protection.102
Addressing barriers to vaccine uptake
Despite clear recommendations and evidence supporting maternal vaccination, coverage in Australia remains suboptimal.103 Uptake is shaped by a complex interplay of psychological, structural and systemic factors. The COVID-19 pandemic highlighted several challenges, such as the amplification of misinformation and the erosion of trust; however, it also introduced opportunities, including the accelerated innovation in health communication and engagement.104-106 To improve maternal vaccination rates, it is essential to understand and address these barriers comprehensively.
Addressing and overcoming vaccine hesitancy
Pregnancy is a time of heightened caution. Many women delay or avoid vaccination because of concerns about vaccine safety for their unborn child, unfamiliarity with newer vaccines, or confusing or inconsistent messaging. The COVID-19 pandemic intensified these hesitations. Rapid vaccine development, the absence of initial trial data for pregnant women, and experiences of coercive public health measures (such as mandates) led some people to feel pressured or mistrustful of authorities.104 Others described wanting more time to learn about vaccines at their own pace, understanding the importance of early, consistent and evidence-based communication.
Clinicians remain the most trusted source of information and can improve transparency and mitigate hesitancy by clearly recommending vaccines while sharing the robust, real-world, ongoing vaccine safety and surveillance data available for maternal immunisations.107,108 This may be achieved by engaging empathetically, addressing specific concerns and reinforcing the safety and benefits of vaccination.109,110 Programs like P3-MumBubVax, now integrated into the NCIRS-led SKAI platform, provide tailored, evidence-based tools to support vaccine discussions in antenatal care.111
Clinician knowledge and recommendations
Healthcare providers significantly influence maternal vaccine uptake. Regular training and updates should be provided to GPs, practice and immunisation nurses, and obstetricians and midwives on the latest immunisation recommendations and communication strategies.112-114 Additionally, healthcare providers should incorporate routine vaccine counselling into all antenatal care visits, supported by clinical decision tools and reminders within electronic medical records.111,115
Reducing systemic and logistical barriers
Barriers to vaccine access during pregnancy include limited availability in antenatal settings, logistical issues such as transport and storage needs, and fragmented care models that can lead to vaccination being seen as another healthcare provider’s responsibility. This is particularly problematic for Australia’s culturally and linguistically diverse (CALD) communities, including First Nation’s and Pacific peoples, and those in rural and remote regions. Integrating vaccines into routine antenatal appointments, and providing maternal immunisation through community pharmacies and mobile clinics, offer flexibility and ease of access to help bridge the gap.116-118 Utilising digital health solutions – such as automated reminders, nudge notifications, and educational tools – can facilitate timely vaccine administration.
Public health initiatives and strategies
Tailored public awareness campaigns addressing vaccine safety, benefits and misconceptions should be specifically designed to include CALD communities. The Vaccine Champions initiative leverages credible healthcare influencers and community healthcare workers to disseminate evidence-based vaccine information and advocate for immunisation within their own networks.119,120 These champions can address vaccine concerns and shift social norms towards vaccine acceptance.
Effective public health communication must recognise these contextual influences. Strategies that combine respectful dialogue, consistent messaging and local engagement are essential to rebuilding trust and improving maternal vaccine confidence post-COVID-19 pandemic.
Future directions and research priorities
To sustain and enhance maternal and infant health protection through vaccination, continued research and development is essential.
Emerging vaccines for pregnant women
Group B streptococcus vaccine
Group B streptococcus (GBS) remains a leading cause of neonatal sepsis and meningitis, resulting in significant morbidity and mortality.121 Several candidate GBS vaccines are undergoing clinical trials to assess safety, immunogenicity and efficacy.122,123 Successful development and integration of a maternal GBS vaccine could substantially reduce neonatal infections.
Cytomegalovirus vaccine
Congenital cytomegalovirus (CMV) infection is a significant cause of birth defects and neurological impairment.124 Research into effective maternal CMV vaccines is ongoing, focusing on safety, efficacy and the potential for widespread implementation.125
Conclusion
Vaccination preconception, during pregnancy and while breastfeeding remains a cornerstone of maternal and neonatal healthcare, significantly reducing the risks posed by VPDs. Despite compelling evidence supporting the safety, efficacy and necessity of maternal vaccination, barriers such as vaccine hesitancy, limited healthcare provider engagement and systemic accessibility challenges persist. Addressing these challenges requires co-ordinated efforts involving healthcare professionals, public health authorities, policymakers and communities.
Continued research into emerging vaccines, such as those targeting GBS and CMV, alongside initiatives aimed at improving vaccine confidence, will be crucial to advancing maternal and neonatal health outcomes. Through enhanced awareness, strengthened clinical recommendations, improved accessibility and supportive public health policies, Australia can ensure comprehensive protection and optimal health outcomes for mothers and their infants. MT
COMPETING INTERESTS: Professor Griffin has received speaker honoraria from Seqirus.
Dr Spence and Dr Armstrong: None.
ACKNOWLEDGEMENTS: The authors would like to thank the reviewers for their considered thoughts and recommendations, strengthening this paper’s readability and applicability.
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