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Short-Term Changes in Your Period After the COVID Vaccine Are Normal, According to a New Study
Times points out, the set of women using the Natural Cycles app isn’t nationally representative—these users tend to be white, educated, thinner than the average American woman, and are not using hormonal contraception, making it difficult to draw generalizable conclusions. Alison Edelman, M.D., a professor of obstetrics and gynecology at Oregon Health & Science University and the lead author of the study, also noted that there’s lots of room for individual variation in the data. For example, a large factor influencing the findings was a group of 380 women who experienced a two-day delay in the start of their period, she told the Times.