Understanding menstrual changes
When it comes to menstruation, normal can be a little difficult to define. What’s typical for one woman might not be for another. For example, while the typical interval from the start of one menstrual cycle to the next is 28 days, a healthy cycle can range anywhere from 21 to 35 days.
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About the Author
Kelly Bilodeau, Former Executive Editor, Harvard Women's Health Watch
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