Your First Period

About your menstrual period

Menstruation, or a woman’s period, is a period of bleeding that happens every month:

  • The average age for girls to begin their periods is 12 years old, but some will begin menstruating earlier or later.
  • Periods vary in length for every girl and can be anywhere from three to eight days.
  • You may experience long cycles (the first day of one period to the first day of the next period) in the first few years of menstruation, but they tend to shorten and become more regular as you age (averaging 28 days in length).

Menstruating, commonly referred to as “having a period,” means that your body is preparing for pregnancy. This includes ovulating (developing and releasing an egg) and preparing the uterine lining for a pregnancy. The uterus is the area of the body where a baby grows during pregnancy.

The period of bleeding you experience is the uterus shedding its lining so that it can prepare a new one each month. The red discharge during your period is the uterine tissue and blood flowing through the cervix and out of the vagina.

Menstrual cycle at a glance

Your period occurs regularly each month, during which you will experience bleeding for approximately three to eight days. It’s normal for many girls to have shorter or longer periods when they first start having menstrual cycles.

Each period signals the start of a new menstrual cycle. A menstrual cycle typically lasts about 28 days. Each menstrual cycle starts on the first day of bleeding and lasts until the first day of bleeding the next month.

Once a young woman has her first period, she will continue menstruating (having monthly periods) until menopause, which occurs around the age of 50.

Signs your period is about to start

Physical changes that show you are entering puberty usually occur prior to beginning your period:

  • Breast growth and tenderness
  • Hair in the pubic area between the legs, as well as in the armpits
  • Lower abdominal cramping, bloating or general discomfort
  • White vaginal discharge

Certain experiences, like breast tenderness or cramping, may also appear again each month right before or during the week of your period.

Preparing for your first period

The age your mother or older sister started her period is a good indication of when you may start your period. Genetic factors are an important influence on the age of menstruation and many girls will begin their periods around the same time as their mother or sisters did.

When your first period starts, you can use either pads or tampons to contain the bleeding. Many girls will start using pads until they are more comfortable inserting a tampon. Whether using a pad or tampon, it’s important to change it throughout the day for comfort and health, and to prevent leaking.

If you think your period may begin soon, carry a supply of pads or tampons in your bag or ask a teacher or nurse for extras. You may also want to keep a sweater to wrap around your waist or a change of clothes on hand in case your period starts and your clothes get stained.

Although your first few periods can be unpredictable and you won’t know the exact day it will start, over time the start of your period will become more consistent. You will then be able to track your menstrual cycle, helping you to be more prepared in the future.

Treatment for period discomfort

During your period, you may experience discomfort, such as cramps (abdominal pain) or headaches. Getting regular exercise and staying well hydrated may help improve these symptoms. A heating pad can also be used to help with abdominal cramps, along with over-the-counter ibuprofen.

Talk to a parent or nurse if you don’t feel good before, during or after your period so you can address any discomfort.

Some girls will experience heavy bleeding, painful and often times debilitating cramps and periods that last longer than one week. Treating cramps with hormone therapy can help alleviate painful periods. Hormone therapy can also help regulate your period if you are experiencing missed periods (going more than two months without having a period), long periods (longer than eight days) or unpredictable bleeding (spotting between periods).