Thousands report unusual menstruation patterns after COVID-19 vaccination

Kathryn Clancy got her first dose of a COVID-19 vaccine in early 2021 and 10 days later found herself sitting uncomfortably in a work Zoom meeting during one of the heaviest periods she’d experienced. “I had what’s often called menstrual flooding,” says Clancy, a biological anthropologist at the University of Illinois, Urbana-Champaign. Clancy wouldn’t have thought to connect the experience to the Moderna dose she’d received were it not for her graduate student, Katharine Lee, now at Tulane University, who shared a similar tale. “I had the worst cramps of my life” after COVID-19 vaccination, Lee says. Intrigued, Clancy—who didn’t experience similarly intense symptoms after her second dose—shared her story on Twitter . Hundreds responded with parallel stories, leading her to suspect a potential link to vaccination. Those suspicions have grown with the completion of a more formal survey in which Clancy, Lee, and colleagues gathered thousands of stories of breakthrough bleeding and bleeding more heavily after a COVID-19 vaccine from people around the world. Between April and October 2021, the survey welcomed anyone 18 and older who gets or used to get a period. Because of that, Clancy cautions, the percentage affected is likely not representative of the general population—and indeed, a whopping 42% of about 16,000 people in the survey who had a regular menstrual cycle said they bled more heavily than usual after vaccination, a number far h...
Source: ScienceNOW - Category: Science Source Type: news