How Long is a Woman's Menstrual Cycle?

The menstrual cycle is the process by which a woman's body prepares itself for reproduction. During this cycle, the uterus thickens and an egg is produced. Then the egg is either fertilized by the sperm of a male, or it breaks up and is expelled with the lining of the uterus during menstruation.

Throughout Life

• A female's menstrual cycle usually begins at age 10 to 14. The menstrual cycle generally ceases around age 50, during menopause.

Normal Length

• Most menstrual cycles last about 28 days. However, they may range anywhere from 21 to 40 days long.

Meauring Your Cycle

• The first day you begin bleeding on your period marks the beginning of your menstrual cycle. The day before you begin bleeding marks the end of a cycle.

Period

• Periods, or menstruation, usually last three to five days, but anywhere from two to seven days is normal. If you experience drastic changes in period length, you may want to go see your doctor.

Fertility

• While the menstrual cycle prepares your body to get pregnant, you are actually only fertile about one day each cycle. This is usually in the middle of your cycle, when ovulation occurs.

Regulation

• You can regulate the length of your menstrual cycle through the use of birth control pills.