The glands in the body and the hormones that communicate between the glands need to be functioning together to then have "regular" menstrual cycling. Remember that a menstrual cycle is defined as the number of days between the first day of bleeding with the last menses and the first day of bleeding with the next menses. The normal menstrual cycle lasts between 21 and 35 days. Changing cycle lengths from month-to-month can be normal. Most women usually bleed for three to seven days. If her bleeding seems excessive, too frequent, lasts more than a week, or if she has other associated symptoms, I would contact her physician.
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