A woman’s period (menstruation) is normal vaginal bleeding that is a natural part of a healthy woman’s monthly cycle. Every month, in the years between puberty (typically age 11 to 14) and menopause (typically about age 51), your body readies itself for pregnancy. The lining of your uterus thickens and an egg grows and is released from one of your ovaries.

If pregnancy doesn’t occur, estrogen and progesterone levels fall, eventually hitting a level that tells your body to begin menstruation. During your period, the uterus sheds its lining and it’s passed, along with some blood, out of the body through the vagina. The average woman loses about two to three tablespoons of blood during her period.

The time between periods (last day to first day) typically averages 28 days, with bleeding typically lasting around 2 to 7 days.

As a woman, your period is your body’s way of releasing tissue that it no longer needs. Every month, your body prepares for pregnancy. The lining of your uterus gets thicker as preparation for nurturing a fertilized egg. An egg is released and is ready to be fertilized and settle in the lining of your uterus.

If the egg is not fertilized, your body no longer needs the thicker lining of the uterus, so it starts to break down and is eventually expelled, along with some blood, from your vagina. This is your period, and once it’s over, the process starts all over again.

The way that women experience their periods vary widely. It’s important that you communicate with your doctor and gynecologist if you have concerns about:

No method guarantees no periods, but, according to a 2014 article in the International Journal of Women’s Health, you can suppress your cycle with various types of birth control such as:

  • Birth control pills. If you take daily birth control pills, after a year you’ll have about a 70 percent chance of suppressing your cycle.
  • Hormone shot. A hormone shot can affect your fertility for up to 22 months. After a year, you’ll have about a 50 to 60 percent chance of suppressing your cycle; about 70 percent after 2 years.
  • Hormonal IUD. One year with a hormonal IUD (intrauterine device) gives you about a 50 percent chance of suppressing your cycle.
  • Arm implant. With an arm implant, your chance of suppressing your cycle is about 20 percent after 2 years.

For a woman to have regular periods, the following need to be functioning properly:

Also some cisgender and transgender — such as AMAB (assigned male at birth) — women do not experience a period.

You period is a natural occurrence. It’s part of your body’s preparation for pregnancy. Every month that you don’t become pregnant, your body expels tissue that it no longer needs to nourish a fertilized egg. If you experience inconsistencies such as a change in your menstrual regularity, frequency, duration, or volume, talk to your doctor or gynecologist.