A study conducted by Linköping University in Sweden has found no evidence that COVID-19 vaccination is linked to a decrease in childbirth rates. The research, published in Communications Medicine, addresses persistent rumours suggesting the vaccines could impair fertility.
"Our conclusion is that it's highly unlikely that the mRNA vaccine against COVID-19 was behind the decrease in childbirth during the pandemic," said Toomas Timpka, professor of social medicine at Linköping University.
The investigation was prompted by widespread claims on social media alleging a connection between COVID-19 vaccines and reduced chances of pregnancy. During the later stages of the pandemic, some countries, including Sweden, experienced fewer births. This led to speculation about possible links to vaccination.
Researchers analysed data from nearly 60,000 women aged 18 to 45 living in Region Jönköping County. Of these women, about 75 percent received at least one dose of a COVID-19 vaccine between 2021 and 2024. The study used healthcare records to examine childbirths, miscarriages, vaccinations, and deaths.
Comparisons between vaccinated and unvaccinated women revealed no statistically significant differences in childbirth or miscarriage rates. These findings align with earlier studies showing no association between COVID-19 vaccines and fertility issues.
"We see no difference in childbirth rates between those who have taken the vaccine and those who haven't. We've also looked at all registered miscarriages among those who became pregnant, and we see no difference between the groups there either," Timpka stated.
The researchers suggest other factors are more likely responsible for recent declines in birth rates. For example, people now reaching their thirties—an age when many have children—were born during the second half of the 1990s when Sweden saw financial difficulties and lower birthrates. This means there are currently fewer potential parents due to demographic trends from three decades ago. Additionally, changes related to health concerns, economic uncertainty, and altered behaviour during lockdowns may have contributed to fewer births.
One notable aspect of this study is its large sample size representative of Sweden’s population. The analysis also accounted for age as a potential confounding factor by adjusting for it accordingly.
Funding for this research came from several sources including the Swedish Research Council.
