Periods are often treated as a monthly inconvenience, but changes in menstrual health can reveal much more than a difficult few days. Severe pain during the reproductive years, unexpected changes in the late 30s or 40s, and bleeding after menopause each deserve a different kind of attention.The tricky part is that these changes are easy to explain away. Pain is called “normal”, poor sleep is blamed on stress, and a little bleeding after menopause is dismissed as harmless. Yet the body can sometimes be giving an important early clue.