A new population-level study from the Czech Republic has found significantly lower conception rates among women who received the COVID-19 injection -- a link once dismissed by Australian regulators and media as a conspiracy theory.
A recently released study using national data from the Czech Republic has found that women aged 18 to 39 who received a COVID-19 injection before conception had substantially lower rates of successful conception -- defined as pregnancies resulting in live births nine months later -- than their uninjected peers.
Published this week by a team of European researchers, the preprint study analysed data from January 2021 to December 2023, covering approximately 1.3 million women. While injection uptake among this age group reached around 70% by the end of 2021, the proportion of live births attributable to injected women remained well below expectations based on their population share.
For instance, in June 2021, although 39% of women took the COVID-19 injection, only 7% of successful conceptions occurred among them. This discrepancy persisted throughout 2022, with uninjected women consistently showing about 1.5 times higher conception rates than their injected counterparts.
The study, led by Vibeke Manniche and colleagues, used anonymised summary data from the Institute of Health Information and Statistics of the Czech Republic (IHIS) alongside COVID-19 injection records. It excluded women who received the injection during pregnancy to isolate the impact of pre-conception injections.
Researchers calculated monthly conception rates per 1,000 women for both groups and found the gap to be consistent and statistically noteworthy across the dataset.
The injections administered were predominantly mRNA-based, with Pfizer-BioNTech's Comirnaty and Moderna's Spikevax making up 96% of doses. The study is one of the first to assess real-world fertility outcomes at a national level in relation to COVID-19 injections.
While the study's findings suggest a significant association, the authors have cautioned against drawing definitive conclusions about causality.
They note that unmeasured factors -- such as differences in contraceptive use, socioeconomic status, health conditions, or personal decisions about pregnancy -- may have contributed. For example, some women might have chosen to delay conception until after injection or may have avoided the injection due to fertility concerns.
Still, the authors argue that such behavioural factors alone cannot fully explain the data, particularly since the national birth rate also declined during this period -- from 1.83 births per 1,000 women in 2021 to 1.45 in 2023.
The study also highlights a possible "batch-dependent safety signal" with certain product batches, a pattern reportedly observed in Denmark, Sweden, and the United States.
Concerns about fertility have been a key source of global hesitancy regarding the COVID-19 injections. Although previous studies and health authorities have generally labelled the products safe for pregnant women, menstrual irregularities and ovarian effects have been documented in some scientific literature.
The Czech study's findings contrast with the narrative promoted by Australian media and authorities, who consistently dismissed concerns about COVID-19 injections causing infertility as "conspiracy theories".
Throughout 2021, outlets like ABC News and AAP FactCheck labeled such claims as misinformation, before any population-level studies had been conducted.
"One persistent rumour undermining confidence in the vaccine is its potential impact on a woman's fertility," ABC News wrote in a 2021 article. "Tracing the COVID-19 myth back to its origins is tricky."
"It appears the lie began with two men," the taxpayer-funded outlet added, before naming Michael Yeadon and Wolfgang Wodarg, whose concerns about injection-induced infertility have now been substantiated via the Czech data.
A 2021 University of New South Wales study reported that over 103 million people worldwide engaged with what it labelled "COVID-19 vaccine misinformation," including infertility "myths" -- with 24% of Australians expressing hesitancy. The researchers called for building "herd immunity against misinformation," even though they lacked large-scale data to directly address concerns like infertility.
Health regulators were unequivocal in affirming that the COVID-19 injections posed no risks vis-a-vis infertility.
On the 9th June, 2021, the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) and the Australian Technical Advisory Group on Immunisation (ATAGI) issued a joint statement recommending that pregnant women be routinely offered the Pfizer mRNA injection at any stage of pregnancy.
"Women who are trying to become pregnant do not need to delay vaccination or avoid becoming pregnant after vaccination," the statement read.
Meanwhile, Australia's health regulator, the Therapeutic Goods Administration (TGA), repeatedly stated that there was "no evidence" that COVID-19 injections caused infertility. In March and May 2021, the TGA's "Is it true?" campaign explicitly debunked the infertility theory.
"None of the COVID-19 vaccines approved for use in Australia cause sterility or infertility," the regulator claimed at the time.
"People who are trying to become pregnant now or who plan to try in the future may receive any recommended COVID-19 vaccines and doses," the TGA added. "COVID-19 vaccination is safe for women who are breastfeeding and women planning pregnancy."
The Australian government applied significant pressure on its citizens to take the COVID-19 injection through workplace mandates, social restrictions, and financial penalties.
Almost 5 million Australian women of childbearing age (15-49) received at least one COVID-19 injection dose in 2021-2022, with approximately 7.5-8.5 million total doses, including "boosters", administered to this group.
According to the latest ABS data, Australia's Total Fertility Rate (TFR) decreased from 1.70 babies per woman in 2021 to 1.50 babies per woman in 2023, a drop of approximately 11.8% over the two years.