Vaccination against a common respiratory virus during pregnancy lowers the risk of severe disease in babies by 74 per cent, but uptake in many countries remains low, a new review suggests.
The report also reveals evidence of lower uptake of the respiratory syncytial virus (RSV) vaccine among some socioeconomic and ethnic groups, those with reduced access to healthcare, and mothers of a younger age.
Despite the value of vaccination in preventing hospitalisation and deaths in young infants, higher uptake is needed to maximise its benefits, experts say.
The findings demonstrate the need for targeted outreach, improved supply chain systems, and robust policies as RSV vaccinations are rolled out globally, they add.
Vaccination against RSV during pregnancy – known as maternal vaccination – has been shown to give babies protection against the virus from the moment they are born.
More than 30 countries have now introduced the maternal RSV vaccine as either a stand-alone intervention or alongside other preventative measures, such as infant immunisation.
Research led by a collaboration between the University of Edinburgh and the University of Granada in Spain combined data from more than 4 million pregnancies between 2023 and 2025, across 16 studies, to estimate the uptake of vaccination programmes.
Since its introduction to the UK in September 2024, at the time the review was conducted, the highest rate of coverage in Scotland was seen in October 2025 with 62 per cent of pregnant women vaccinated. England achieved its highest vaccination rate of 58 per cent in August 2025.
The United States had some of the lowest overall uptake, with an estimated 27 per cent vaccinated during the first year RSV maternal vaccine was available, which is delivered alongside other preventative interventions.
The research team note that these figures are lower than for other maternal vaccines, such as whooping cough, in the same period.
The report also provides valuable population-level evidence on vaccine safety, with no evidence of an increased risk of preterm birth in those vaccinated at 32-35 weeks pregnant, based on data from more than 16,000 pregnancies.
As more countries introduce RSV prevention programmes, analysing the emerging real-world evidence is necessary to monitor the impact of vaccination, support policy makers, healthcare workers and pregnant individuals, and inform future vaccination campaigns, experts say.
The study is published in the journal The Lancet Regional Health - Europe: https://www.thelancet.com/journals/lanepe/article/PIIS2666-7762(26)00259-0/fulltext [URL will become active after embargo lifts]. The research team also included colleagues from Public Health Scotland, the Pan-American Health Organization (PAHO/WHO) and inputs from six other UK-based universities.
Dr Ting Shi, from the University of Edinburgh's Usher Institute, said: "We found the vaccine reduced the risk of RSV-related hospitalisation in babies under six months by around 74 per cent, which lines up well with what the clinical trials predicted, and we found no evidence of an increased risk of preterm birth. But uptake during the first vaccination seasons was low. Timing matters too. The vaccine works best when it's given at least two weeks before birth, so making sure women can access it early in their eligibility window is key. The vaccine itself looks safe and effective – the next challenge is making sure everyone who could benefit actually gets it."
Dr Evelyn Balsells, University of Granada, said: "Research shows that RSV vaccination during pregnancy protects babies. Efforts to increase uptake and reduce disparities will be essential to maximise the benefits of maternal RSV vaccination."
Dr Kimberly Marsh, Viral Respiratory Pathogens lead, Public Health Scotland, said: "This review shows that maternal RSV vaccination is protecting babies from severe illness but uptake is not equal across all communities. Monitoring vaccine coverage and addressing barriers faced by some ethnic groups and more deprived communities will be important to ensure that all families can benefit from protection the RSV vaccine offers to babies."
