National Health & Safety A Possible Side Effect? Thousands Of People Saw Menstruation Changes Post-Vaccine 6:39pm August 03, 2021 by Geoff Brumfiel Health Medical Treatments National Share URL copied to clipboard! Copyright 2021 NPR. To see more, visit https://www.npr.org. 300x250 Ad More All Things Considered Health & Safety A special shoutout to fathers by Scott Detrow World News Copenhagen's climate preparedness projects by Scott Detrow 300x250 Ad Support quality journalism, like the story above, with your gift right now. Donate