Knowing the length of your menstrual cycle is helpful information to have when you are pregnant, so you can more accurately calculate your baby's due date. To calculate the length of a menstrual cycle you need nothing more than a calendar and a month in which to track your cycle. Keep a sharp eye out for both the beginning and ending of your cycle to get an accurate idea of how long it is, and track your cycle each month so you always know how long your monthly menstrual cycle is.
Step 1
Print a monthly calendar from CalendarLabs.com, or use an existing calendar that you already have. For accuracies sake, print out the correct month so that you can mark down the correct dates for your cycle beginning and ending.
Step 2
Circle the day that your menstrual bleeding begins, recommends Ovulation-Calculator.com. This is likely the day after your most severe premenstrual symptoms, when you being to see light spotting as the start to your period.
Step 3
Mark each of the days in passing between periods with an 'x,' including the days during which you have a period.
Step 4
Draw another circle around the day that you begin bleeding and start menstruation again.
Step 5
Count the days in between the circled numbers, including the first circled number but not the second. The number of dates is the length of your menstrual cycle.
Step 6
Start again each month so that you can correctly calculate the length of your menstrual cycle each month; the number of days may vary for each cycle.
Tips and Warnings
- Remember that there is a wide range of "normal" when it comes to the length of your menstrual cycle, notes WomensHealth.gov. A teen's cycle is usually between 21 and 45, and an adult's menstrual cycle is usually between 21 to 35 days. Make an appointment with your gynecologist if you have any concerns.
Things You'll Need
- Calendar
