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Teen Girls' Health

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Girls and Puberty

Your First Menstrual Period

Soon after they develop breasts, most girls have their first menstrual period. This usually happens between ages 12 and 13, but menstruation can start earlier or later. During a menstrual period, there are two to three days of heavier bleeding with two to four days of lighter flow.

Menstruation happens to all girls, so try not to be embarrassed in learning more about it. Talk to your mom or an adult you trust about having your period.

During your period, you'll need to wear a sanitary pad or tampon. Your mom (or other adult) can purchase these products and show you how to use them. Be sure to keep extra pads or tampons in your school locker in case your period starts suddenly during the school day. If you forget, ask to see a school nurse or ask a female teacher for help.

Cramps and Your Period

Cramps are caused by the increased production of hormones during your period. This causes the muscles of the uterus to contract. You might also notice:

  • Aching in your upper thighs
  • Back pain
  • Bloating
  • Nausea
  • Diarrhea
  • Fatigue

Medications such as ibuprofen (Advil) and acetaminophen (Tylenol) can help ease period pain. Putting a heating pad or hot water bottle on your abdomen may also help. If your cramping is severe, talk to your health care provider.

Girls and Mood Swings

Because of the surges in hormones during puberty, many girls feel moodiness at times, especially right before their periods. This is called premenstrual syndrome (PMS). PMS may cause:

  • Irritability
  • Difficulty sleeping
  • Fluid retention
  • Anxiety
  • Dietary cravings

Once your period starts, the PMS symptoms usually disappear. It's helpful to exercise during PMS and your period in order to boost your mood and help you feel your best. If your mood is lower than normal, talk to your health care provider about your feelings.

Some girls have a decrease in self-esteem and body satisfaction if they hit puberty earlier than their friends. Other girls feel different if they enter puberty later than their friends do. That's why it's important to understand what's happening to your body, and realize that every girl goes through the same changes -- some sooner, some later. But if you have not gone through puberty by age 14, including menstruating, you should see your health care provider.

It's important to eat a balanced diet, exercise daily, get plenty of sleep, and stay at a healthy weight during this time. Continue to see your primary health care provider for regular checkups, so you can feel your best and have someone knowledgeable to go to with your questions or coincerns.


WebMD Medical Reference

Reviewed by Amita Shroff, MD on March 04, 2014

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