COVID-19 Vaccine: Swedish Study Finds No Link to Lower Birth Rates
- Persistent online rumors linking COVID-19 vaccines to reduced fertility have been largely debunked by a growing body of scientific evidence.
- Published in Communications Medicine on February 8, 2026, the research analyzed data from nearly 60,000 women aged 18 to 45 in Jönköping County, Sweden, between 2016 and 2024.
- Researchers followed childbirth and miscarriage rates, comparing outcomes between vaccinated and unvaccinated women.
Persistent online rumors linking COVID-19 vaccines to reduced fertility have been largely debunked by a growing body of scientific evidence. A recent, large-scale study from Sweden adds further reassurance, finding no association between COVID-19 vaccination and childbirth rates or miscarriage rates.
Published in Communications Medicine on , the research analyzed data from nearly 60,000 women aged 18 to 45 in Jönköping County, Sweden, between and . The study aimed to address concerns that had circulated, particularly on social media, suggesting that mRNA vaccines could impair a woman’s ability to become pregnant or increase the risk of miscarriage.
Researchers followed childbirth and miscarriage rates, comparing outcomes between vaccinated and unvaccinated women. Approximately 75.5% of the women included in the study received at least one dose of a COVID-19 vaccine – primarily mRNA vaccines like Comirnaty, Vaxzevria, or Spikevax – between and the end of the study period. The study accounted for potential confounding factors, such as age, and used sophisticated statistical modeling to assess the relationship between vaccination and reproductive outcomes.
No Evidence of Impact on Childbirth or Miscarriage
The findings were clear: COVID-19 vaccination was not significantly associated with a change in childbirth rates. Adjusted hazard ratios, a measure used to assess the relationship between exposure and outcome, were close to one, indicating no meaningful difference between vaccinated and unvaccinated groups. Similarly, no significant association was found between vaccination and miscarriage rates.
The researchers also conducted sensitivity analyses, adjusting for different estimations of pregnancy duration, to ensure the robustness of their findings. These analyses consistently showed no link between vaccination and adverse reproductive outcomes. Approximately 10% of participants gave birth after receiving a booster dose, and less than 1% experienced a miscarriage during the vaccination period.
Contextualizing Declines in Birth Rates
The study acknowledges that some countries, including Sweden, did observe a decline in childbirth rates during the pandemic. However, the researchers emphasize that these declines are more likely attributable to broader societal and economic factors related to the pandemic, rather than to vaccination. These factors include changes in behavior associated with lockdowns, pandemic-related socioeconomic conditions, and shifts in individuals’ intentions regarding family planning.
“Our conclusion is that it’s highly unlikely that the mRNA vaccine against COVID-19 was behind the decrease in childbirth during the pandemic,” says Toomas Timpka, professor of social medicine at Linköping University, as reported by Linköping University news services. Historical trends also suggest that declining birth rates in Sweden have been occurring for decades, linked to factors such as reduced social support for families and economic pressures.
Addressing Persistent Misinformation
The emergence of misinformation regarding COVID-19 vaccines and fertility highlights the importance of rigorous scientific investigation and clear communication of research findings. Early in the pandemic, unfounded claims circulated online, suggesting that the vaccines could cause infertility by triggering an immune response against a protein found in the placenta. These claims were not supported by scientific evidence, and multiple studies have since refuted them.
This Swedish study adds to the growing body of evidence demonstrating the safety of COVID-19 vaccines with respect to reproductive health. Researchers at Linköping University analyzed healthcare records from to , and found no statistically significant difference in childbirth or miscarriage rates between vaccinated and unvaccinated women. A similar study, as reported by News-Medical.net on , also found no link between vaccination and reduced fertility.
Study Limitations and Future Research
The researchers acknowledge some limitations to their study. Relying on childbirth records to identify pregnancies may introduce a degree of selection bias, particularly for early pregnancy losses that may not be captured in healthcare registries. They also note that the study focused on a single region of Sweden, although the population studied is considered representative of the broader Swedish population.
Despite these limitations, the study provides compelling evidence against a causal link between COVID-19 vaccination and reduced fertility. Further research may continue to monitor reproductive outcomes in vaccinated and unvaccinated populations, but the current evidence strongly supports the safety and efficacy of COVID-19 vaccines for individuals planning to conceive or during pregnancy.
The findings underscore the importance of relying on credible sources of information and consulting with healthcare professionals for accurate guidance on vaccination and reproductive health.