How to determine your menstrual cycle

It's important to know how long your menstrual cycle is. A missed period is often the first symptom of pregnancy you'll notice. Stress, poor nutrition, hormonal changes and abnormalities in your uterus can cause irregular periods, although women can miss an occasional period or have some variation in their cycle when nothing is wrong at all. When you visit your doctor, even for a routine visit, he will likely ask about the length and duration of your cycle to ensure that everything is normal. Determining the length of your cycle is simple.

Things You'll Need

• Calendar
• Pen

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Instructions

Chart your cycle

• 1

  The first day that you begin to bleed is the first day of your menstrual cycle. Mark this day on your calendar.

• 2

  Make a check mark on each day that bleeding continues.

• 3

  Repeat this process every time you get your period, for at least three months.

• 4

  Count the days that you have bleeding. If the numbers vary each month, average them. Add the number of days together, and divide that by the number of periods you had. If you tracked four periods and two lasted six days, one lasted four days and one lasted five days, you would divide 21 by four to get 5.25 days. Your periods average about five days.

• 5

  The length of time between the beginning of one period and the beginning of the next is the length of your menstrual cycle. Count how many days there are, and if the numbers differ from month to month, average them as well.