Europe must act now to strengthen maternal vaccination in pregnancy and ensure all women and babies can benefit from a new generation of vaccines to protect against serious infections. That is according to a new Lancet Regional Health - Europe Series led by Professor Asma Khalil at City St George's, University of London, which is being launched and presented today at the 2026 Global Society for Maternal-Fetal Medicine Congress in Utrecht.
The Series found maternal RSV vaccination was associated with an approximately 74% lower risk of hospitalisation for RSV-related lower respiratory tract infection in babies younger than six months. However, evidence also suggests substantial inequalities in access, with one UK study finding women living in the most deprived areas had 72% lower odds of receiving vaccination than women living in the least deprived areas.
While scientific advances in maternal immunisation are moving rapidly, health systems have not kept pace. Fragmented delivery models, unequal access, gaps in surveillance and uncertainty over responsibility for vaccine delivery continue to limit uptake and leave many women and babies without protection, all of which need to be tackled head-on in a coordinated manner.
Professor Asma Khalil, Professor of Obstetrics and Maternal Fetal Medicine in the School of Health & Medical Sciences at City St George's, University of London, and Chair of the Series, said:
"Maternal vaccination is one of the most powerful public health interventions, giving protection to both pregnant women and their babies from serious infectious diseases. We now have new vaccines becoming available and other vaccine candidates progressing through clinical development, but introducing a vaccine is only the first step. Women need timely access, trusted information and convenient services if these programmes are to achieve their full benefit.
"Across Europe we continue to see substantial variation in uptake and persistent inequalities in access. Our Series shows that countries should begin preparing now for the next generation of maternal vaccines rather than waiting until new programmes are introduced."
Maternal RSV vaccination significantly reduces infant hospitalisations
Respiratory syncytial virus (RSV) is a common cause of a type of chest infection called bronchiolitis, but it can cause breathing problems and may require treatment in hospital. A systematic review and meta-analysis included in the Series found maternal RSV vaccination was associated with an approximately 74% lower risk of hospitalisation for RSV-related lower respiratory tract infection in babies younger than six months.
The pooled analysis of 16,394 pregnancies did not identify a statistically significant association between maternal RSV vaccination and preterm birth. Continued safety monitoring remains important as vaccination programmes expand.
The findings provide reassurance about the real-world effectiveness of maternal RSV vaccination, while reinforcing the importance of delivering vaccination within the recommended gestational window, with sufficient time before birth for protective antibodies to develop and transfer to the baby.
However, evidence presented in the Series suggests not all women are benefiting equally. One UK study included in the review found substantial lower maternal RSV vaccination uptake among women living in the most deprived areas (a 72% lower odds) than among those living in the least deprived areas.
New vaccines are coming but health systems must be ready
The Series also highlights a growing pipeline of maternal vaccines that could help protect pregnant women from serious infections as well as newborn babies during the first weeks and months of life.
A different paper in press for the Series, led by Professor Paul Heath from City St George's, examines the next generation of maternal vaccines in development. Among the most advanced candidates are vaccines against group B streptococcus (GBS), a leading cause of neonatal sepsis and meningitis worldwide.
The authors argue that countries should begin preparing now for future maternal immunisation programmes, including strengthening surveillance systems, developing delivery pathways and supporting healthcare professionals to discuss vaccination confidently with pregnant women, all before new vaccines receive regulatory approval.
Professor Paul Heath, Professor of Paediatric Infectious Diseases at City St George's, University of London, said:
"We are entering a new era for maternal immunisation. For decades we have understood the value of protecting mothers and babies through vaccination during pregnancy, but we are now seeing a pipeline of new vaccines that could prevent serious infections in the earliest months of life."
"The science is advancing quickly. The challenge now is ensuring health systems are ready to deliver these vaccines effectively, monitor their impact and make sure all families can benefit, regardless of where they live or what their circumstances are."
Call for coordinated action across Europe
In another paper in press for the Series, maternal vaccination policies were mapped across all 53 countries in the World Health Organization (WHO) European Region and reviewed 163 studies and policy sources.
Common factors associated with higher uptake include when vaccines are free at the point of care, offered as part of routine antenatal services, delivered by healthcare professionals with clear responsibility for recommending and administering vaccines, and supported by robust monitoring systems.
However, barriers including additional appointments, language difficulties, fragmented services and inconsistent recommendations continue to limit access for some women and families.
Experts highlight evidence of persistent inequalities in maternal vaccine uptake and say that coverage should be routinely monitored by factors including deprivation, ethnicity and migration status so that underserved communities are not left behind as new programmes are introduced.
As new maternal vaccines are introduced, the Series shines a light on the importance of robust surveillance systems. A review accepted for publication of maternal pertussis vaccination programmes across seven European countries found substantial differences in how disease burden, vaccine uptake and programme impact are monitored. Researchers argue that stronger and more consistent surveillance systems will be essential as maternal immunisation programmes expand, helping policymakers understand vaccine effectiveness, safety and emerging inequalities.
'The Future of Maternal Vaccination' Series therefore calls for:
- maternal vaccination to become a routine component of antenatal care across Europe
- stronger monitoring of vaccine uptake, safety and inequalities
- better integration of maternity and immunisation records
- improved support for underserved communities
- coordinated preparation for future maternal vaccine programmes
- establishment of a European coordination group for maternal vaccine rollout
- development of a European Maternal Immunisation Preparedness Plan.
Strengthening vaccine safety assessment
Another focus of the Series is on vaccine safety assessment during pregnancy. It explores the WHO's new causality assessment approach, which is designed to help assess whether a health event in pregnancy occurring after vaccination may be related to vaccination or has another explanation.
Consistent assessment is essential for identifying potential safety signals and providing clear, trustworthy information to families.
Miscarriage, preterm birth and hypertensive disorders can occur during pregnancy regardless of vaccination status, and an event occurring after vaccination does not by itself establish that the vaccine caused it.
The authors note that structured safety assessment should complement wider surveillance systems, clinical studies and pregnancy registries as maternal vaccination programmes expand.
Closing evidence gap in pregnancy research
The Series also highlights continuing challenges in generating evidence during pregnancy.
A review of vaccine research found that almost 95% of late-stage vaccine trials conducted between 2018 and 2023 explicitly excluded pregnant participants, limiting the availability of evidence directly relevant to pregnancy.
The Series supports greater inclusion of pregnant women in research, alongside robust systems for evaluating vaccine safety during pregnancy and monitoring outcomes for mothers and babies.
Professor Asma Khalil added:
"The evidence is clear that maternal vaccination can save lives and reduce serious illness in mothers and babies. Our challenge now is ensuring that these benefits reach all families, regardless of where they live or their circumstances. Achieving that will require coordinated action across health services, public health agencies and policymakers."
