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What happens during your menstrual cycle

The menstrual cycle includes not just your period, but the rise and fall of hormones and other body changes that take place over the weeks in your cycle. Want to know what happens on each day of the cycle? Check out the cool tool below.

Our tool is based on a sample 28-day menstrual cycle, but every woman is different in how long her bleeding periods last and how many days come between them. Keep reading to learn more about your menstrual cycle.

(If the tool above does not appear, please take a look at our text version of this tool.
Viewing the above requires the Adobe Flash Player.)

At first, your periods may not be regular. For example, you may have two in one month, or have a month without a period at all. Periods will become more regular in time. If you’re concerned about your cycle, learn about problem periods.

Every woman has her own period pattern. To learn about yours, keep track of your periods on an app or calendar. Keeping track will help you to better know when to expect your next period and if you have missed one.


Content last reviewed April 15, 2014
Page last updated May 27, 2014