COVID-19 vaccines do not cause disruptions to women’s periods, a new study suggests.
Research led by the University of Edinburgh found that catching the virus can lead to some changes, such as missed or heavier periods, or bleeding between periods.
But the study also found that the vaccine appears to have no effect when vaccinated and unvaccinated people are compared.
Here’s what the study found
Researchers surveyed almost 5,000 pre-menopausal vaccinated women in the UK, in March 2021.
The results found that 82% of women reported no menstrual changes.
While 6.2% reported more disruption during their period cycles and 1.6% reported less disruption.
Around 10% reported changes, including the cycle length and regularity of their periods, as well as the amount of menstrual bleeding.
The women who reported changes – 18% – were at higher risk due to smoking, previously caught COVID-19, or were not using oestradiol-containing contraceptives such as the combined contraceptive pill.
The researchers also looked at a wider group of 12,579 vaccinated and unvaccinated women.
The group included 3,635 vaccinated women who have never had COVID-19 and 1,354 who had the virus.
The study also observed 1,802 unvaccinated women who had the virus in the past and 5,788 women who were neither vaccinated nor previously diagnosed with COVID-19.
So, what was the outcome?
The results found that vaccination alone did not lead to increased changes to periods.
However, those with a history of the virus reported an increased risk of heavier bleeding, missed periods and bleeding between periods.
Dr Jackie Maybin, one of the study authors from the University of Edinburgh, said: “These results rely on people recalling their previous menstrual experiences, and may include bias due to those who chose to complete the survey.
“Nevertheless, our results are reassuring that COVID-19 vaccination does not cause concerning menstrual changes, and helpful for identifying people who might be at higher risk of experiencing menstrual disturbance.”
The group of researchers hope the results will help healthcare professionals discuss the risk of period issues linked to COVID-19 vaccines.
The study was led by the University of Edinburgh and published in the journal iScience.
Researchers from universities in Edinburgh, Montpellier, Oxford, Bristol and Exeter examined the survey results.