(July 15, 2022)

A study found that 42% of people with regular menstrual cycles said they bled more heavily than usual after their Covid vaccination.

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The new survey started in April 2021, around the time people began to report unexpected bleeding and heavier flow post-vaccine. However, these anecdotes were at the time met with the rebuttal that there was no data linking menstrual changes to vaccination.

That was both true and indicative of a larger problem. Individuals who took part in Covid vaccine trials were not asked if they experienced menstrual changes.