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Analyses showed a small increase in the percentage of participants who experienced greater total bleeding quantity following the first COVID-19 vaccine dose compared with an unvaccinated comparison group. Photo Credit: Obi |
A new international study finds that women vaccinated for COVID-19 have a slightly higher risk for a heavier period after vaccination.
The study, led by Oregon Health & Science University reproductive health services researcher Blair Darney, Ph.D., M.P.H., and physician-scientist Alison Edelman, M.D., M.P.H., published in the British Journal of Obstetrics and Gynaecology. These findings build on prior work from the same research team that first identified an association between COVID-19 vaccines and menstrual cycle changes.
While there is a growing body of evidence demonstrating that COVID-19 vaccination is associated with a small increase in cycle length, other disturbances such as bleeding quantity are less well known. This study aimed to estimate the effect of COVID-19 vaccination on menstrual bleeding quantity among individuals with normal menstrual cycles.
“Menstruation is a routine bodily function and a key indicator of overall health, so it’s crucial that we understand the scope of this issue among the global population,” said Edelman, one of the study’s lead authors. “The more we can understand about these reported changes, the more effectively we’re able to counsel individuals about what to expect with a COVID-19 vaccine and how to make an informed decision about getting vaccinated.”