Norway's Maternal Vaccination Gap: Under 30% for Flu, Under 13% for COVID-19

Vaccination during pregnancy protects two people at once - the mother and the newborn, who arrives in the world without a developed immune system and unable to receive most vaccines for the first weeks or months of life. The World Health Organization recommends a 75% vaccination coverage target for at-risk groups against both influenza and COVID-19. In Norway, the actual figures for the 2023/24 season were 29.9% and 12.1%, respectively.

Those numbers come from a detailed registry-based study of 53,161 women who gave birth in Norway between October 2023 and September 2024. The research, conducted by Stecher and colleagues at the Norwegian Institute of Public Health and published in Eurosurveillance, links data from two national registries - the Medical Birth Registry Norway and the Norwegian Immunisation Registry - to track who was vaccinated, when, and at what stage of pregnancy.

A population with high trust but low uptake

Norway is an unusual setting for low vaccination coverage. The country has a well-funded public health system and a population with consistently high levels of trust in health authorities and official recommendations. Yet that trust has not translated into maternal vaccination behavior, at least not for respiratory viruses. The study authors point to practical and psychological barriers that may outweigh general trust in any given encounter with the health system.

In Norway, the influenza vaccine during pregnancy is available by self-initiated appointment and carries a cost. The COVID-19 vaccine is free but also accessed through self-referral. Neither is integrated into routine prenatal appointments. A pregnant woman must actively seek out vaccination rather than encounter it as a default part of her prenatal care. That design choice may explain a great deal of the gap between recommended and actual coverage.

Who was - and was not - vaccinated

Coverage varied substantially by age and region. Women aged 25 and younger had the lowest uptake of both vaccines across the board. Regionally, Oslo and Vestland counties had the highest vaccination rates, while Northern Norway recorded the lowest. The authors note that geographic, socioeconomic, and cultural factors likely contribute to those patterns, though the registry data cannot fully explain the mechanisms.

Only 11.4% of women received both vaccines, meaning that even the relatively small proportion who did get vaccinated often received only one of the two. That dual-vaccination rate is particularly low given that influenza and COVID-19 together represent the primary respiratory virus risks during pregnancy for which vaccines exist.

For influenza specifically, just 22.3% of women received the vaccine during the second or third trimester - the recommended window. Coverage peaked among women delivering in February, reaching 50.8%, then declined steadily. The pattern for COVID-19 vaccination followed a similar curve, with 10.1% vaccinated during the recommended trimester window.

Why this population faces elevated risk

Pregnant women are physiologically vulnerable to severe outcomes from influenza and COVID-19. Changes in immune function, lung capacity, and cardiovascular load during pregnancy increase the probability of serious illness compared to non-pregnant adults of the same age. Their newborns are also at risk: infants under six months cannot receive influenza vaccines, meaning maternal vaccination is the primary mechanism for passing protective antibodies to the baby before birth.

Despite decades of evidence supporting maternal vaccination against influenza, and more recent evidence supporting COVID-19 vaccination in pregnancy, the 2023/24 data suggest that most pregnant women in Norway were not reaching the vaccination threshold where that protection could function as intended.

What could move the needle

The study authors point to international evidence suggesting one intervention with demonstrated impact: integrating vaccination directly into routine prenatal care. Norway introduced whooping cough vaccination for pregnant women as part of its maternal immunisation programme, and coverage improved substantially once the vaccine became a standard component of prenatal visits rather than a separate action women had to initiate themselves.

The same logic likely applies to influenza and COVID-19. When vaccines require active self-referral and, in the case of influenza, a co-payment, utilization falls particularly among younger and lower-income populations. Removing the cost of influenza vaccination and embedding both vaccines into scheduled prenatal appointments would address multiple barriers at once.

The authors also highlight the need to identify information sources that pregnant women already trust. Hesitancy in this population is not uniform - it is shaped by misinformation, uncertainty about fetal safety, and a general reluctance to take anything during pregnancy that is not explicitly required. Tailored communication that addresses those specific concerns, delivered through healthcare providers during existing appointments, may achieve more than broad public health messaging.

Limitations of the registry approach

Registry-based studies offer reach and scale that clinical trials cannot match - 53,000 women represents almost the entire Norwegian birth cohort for the study period. But registries cannot capture why women did or did not get vaccinated, what information they received from their providers, or whether they were advised against vaccination for medical reasons. The study also does not follow maternal or infant outcomes, so it cannot quantify how much the vaccination gap translated into preventable illness.

The authors call for both more targeted strategies and better surveillance of maternal vaccination going forward. Similar gaps have been documented across Europe and internationally, suggesting this is not a Norway-specific problem but a structural challenge in maternal immunization programs globally.