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Categories > Menstrual Health > Menstrual cycle

Check the calendar

When your doctor talks to you about your menstrual period and your menstrual cycle, he or she is speaking of two different entities. Your menstrual period refers to the days you bleed. About half of all women bleed for three to four days, while 35 percent bleed for five or six.

Your menstrual cycle is the span of time from the first day of one period to the start of the next. The length of the cycle can range from 21 to 35 days, with 29 being the average.

Knowing your normal menstrual cycle will help you detect any unusual changes. Here are a few ways to help you keep track:

  • Keep a calendar. Buy a little date book that you can tote easily in your purse. Note when your period starts and ends and the type of flow you had. Was it heavy or light? Keep tabs on how you feel throughout the month.
  • By the numbers. When calculating the length of your menstrual cycle, make sure you count properly: Begin counting on the first day of your period and continue until the day your next period starts. For example, if you have a 29-day cycle, day one is the first day of your period and day 29 is the day before your next period begins.
  • Investigate. If you notice any discomfort or differences in your cycle length or flow, take your calendar to your doctor and talk with him or her about it. A change in your menstrual pattern doesn’t always mean there’s cause for concern, but only your physician can tell if these changes are normal for you.