As women report changes in their menstrual cycles due to Covid-19 vaccines, a study has finally been done to find out if this is actually the case.
Menstrual cycles have long been an underestimated sign of health.
That all changed in early 2021, however, when people started noticing that their menstrual bleeding was different after being vaccinated against Covid-19.
While not everyone’s cycle changed, or most people’s periods returned to normal after a couple of months, there was one obvious question that scientists had to answer.
How many people experienced changes in their menstrual cycle after vaccination against COVID-19?
About 42 percent, according to a new study published in Scientific achievements In the course of which 39,129 fully vaccinated adults were interviewed for three months, aged 18 to 80, who had not yet been ill with Covid-19.
What were the participants asked?
Participants were asked about changes they noticed in their menstrual cycles after vaccination. For example, their menstrual cycle, cycle length, bleeding time, and general menstrual symptoms.
In addition, they were required to provide information about their reproductive history (eg, pregnancy history), general reproductive conditions associated with altered menstrual bleeding patterns (eg, endometriosis, PCOS), and other treatments (eg, sex-confirming hormones, IUDs). ).
What did the researchers find?
The study showed that:
• About 42 percent of women with regular menses bled more than usual after vaccination, and 44 percent reported no change after vaccination. A much smaller proportion of people have experienced lighter periods.
• Participants who do not normally menstruate due to menopause or use of reversible contraceptives or sex-affirming hormones also experienced breakthrough bleeding.
• Those who bled more than usual after receiving COVID-19 vaccines were likely to be older, self-identified as Hispanic or Latino, or have pre-existing medical conditions such as endometriosis.
Any changes in menstrual bleeding do not indicate changes in fertility.
“Generally, changes in menstrual bleeding are not unusual or dangerous, but attention to these experiences is needed to build confidence in medicine,” the researchers wrote in Friday’s issue of the journal. Scientific achievements magazine.
Based on their findings, Li and her team suspect that Covid-19 vaccines may target inflammation in the body rather than altering ovarian hormonal pathways.
They came to this conclusion because the difference between those who had a menstrual cycle and those who did not take hormonal contraceptives was minimal.
Why is this study revolutionary?
Often, clinical trials focus on whether Covid-19 vaccines are safe for pregnant women and whether they affect fertility. However, they usually do not follow up on respondents for more than a week after they receive the Covid-19 vaccine and do not ask them for more information about their menstrual cycles.
According to Katherine Lee of the University of Washington School of Medicine and her colleagues, this meant that Covid-19 vaccine manufacturers “have not been able to determine the extent to which this observation was a coincidence or a potential side effect of the vaccines.”
Originally published as Study shows Covid-19 injections affect menstrual cycle