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Puberty for Girls

Puberty is the time when your body grows into a woman's body. The changes in your body make it possible for you to have babies if you have sex.

How does puberty start?

Puberty starts with changes in your hormones. Because of a change in hormones released from your brain, your ovaries start making estrogen hormone. The ovaries are part of your reproductive system. They make eggs and also the female hormone progesterone. Estrogen is the main hormone that starts the changes that happen when girls go through puberty.

When does puberty start?

Girls may start puberty as early as age 7 or 8 years or as late as age 14.

How do I know when puberty has started?

The first thing you will notice will be growth of your breasts. At first, there is just a little swelling below the nipple. It may take 4 or 5 years for your breasts to fully develop.

You will start having pubic hair between your legs, in your genital area. You will also start having hair under your arms and more hair on your legs. You will have more body odor, so you may want to bathe more often or start using deodorant.

Your body will also start to change shape. Your hips will get wider and you will have body fat in new places on your body. Sometimes girls have trouble accepting their changing body shape. However, these changes are important for your health and they are a normal part of growing up. You will also gain weight during this time. This is normal. If you are worried about gaining weight, talk with your healthcare provider about it.

Many changes take place inside your body, too. Because of changes in your vagina (the birth canal), you may start having a small amount of white discharge. This is normal. The vagina and uterus will get bigger. The uterus is where babies grow if you are pregnant. Inside the uterus, blood vessels and tissue will start to develop, eventually leading to your first menstrual period.

Girls usually have a growth spurt 1 to 2 years after puberty starts and about 6 months before they start having periods. A growth spurt is when your body grows a lot in a short time. You will probably not grow much taller after you start having periods. However, your bones will keep getting stronger. This is why it’s important to have 4 to 5 servings every day of foods that have lots of calcium. Calcium helps build strong bones, so you have less of a chance of having osteoporosis (weak bones) when you are older.

What is a menstrual cycle?

Girls are born with all of their eggs (about 2000 or so). The eggs are stored in the 2 ovaries. Each month before you have a period, an ovary releases an egg. This is called ovulation. The egg travels through a tube called the fallopian tube into the uterus. Hormones make the lining of the uterus thicker to get the uterus ready for a baby in case the egg is fertilized by sperm from a man. Some girls have pain in the lower part of their belly during ovulation.

If a man's sperm does not fertilize the egg, the uterus sheds the lining it prepared for a baby a couple weeks after ovulation. When the uterus sheds its lining, blood flows out of your vagina. This is called menstrual flow, or your period.

After each period, the monthly menstrual cycle starts again.

What else should I know about periods?

For the first year or two, you may have a period anywhere from once a month to 3 times a year. Then your periods will start being more regular and you will have a period every month.

You may want to carry a tampon or pad with you so you are ready before your first period starts. Often your first period happens about 2 and 1/2 years after your breasts start developing. The average age for a girl's period to start is 12, but some girls start their periods as early as age 8 or as late as 16. If you get your period earlier than age 8 or you still haven't had a period by the time you are 17, you should talk to an adult or your healthcare provider about it.

When your periods are regular, you may have them every 22 to 35 days. Periods usually last 3 to 7 days. Pads or tampons help absorb the blood that comes out. It may seem like a lot of blood, but it’s usually only about 2 to 5 tablespoons with each period.

Some girls have painful cramps in the lower part of their belly during their period. Cramps are caused by the muscles tightening in your uterus as the lining is shed during your period. You may have pain for only a day or it may last all the time you have bleeding. Taking acetaminophen or a nonsteroidal anti-inflammatory pain medicine (NSAID) like ibuprofen usually helps. If it doesn't help, ask your healthcare provider about stronger medicine. Unless recommended by your healthcare provider, don’t take nonsteroidal anti-inflammatory medicines (NSAIDs) for more than 10 days for any reason. NSAIDs, such as ibuprofen, naproxen, and aspirin, may cause stomach bleeding and other problems. Read the label and take as directed.

What is masturbation?

During puberty you may start to have sexual feelings because of the new hormones in your body. You may find that touching or rubbing your genital area feels good. Touching this part of your body is called masturbation. Many girls masturbate. It’s a natural way to explore your body and is quite normal. People often joke about it, but it’s important to know that there are no bad things that happen from masturbating.

What about acne?

One part of puberty that teenagers don't like is acne. You may have heard that acne is caused by not washing your face or from eating greasy food or sweets. There’s no proof that these things cause acne. It’s caused by your changing hormones and is a normal part of growing up. Some girls may not have much acne, but for others it may be worse. You can get medicines to treat mild acne without a prescription. If your acne seems to be more serious, you may want to see your healthcare provider for medicine to help treat it.

What are the emotional changes of puberty?

As you go through puberty you start to have a lot of different feelings. You are trying to figure out your place in the world. You become more independent and start doing things without your parents. You may be influenced by your friends' ideas and feel pressure to do things that you may not agree with, like using drugs or alcohol. This is a time to start sorting out your values and decide what is right and wrong.

As part of this, you may start having romantic feelings for someone. You may start dating. You may feel like you are in love one day and not the next. It’s natural to have feelings that change quickly. You may start thinking about having sex. Take time to think through your decision before you have sex. You need to think about the physical and emotional risks you will be taking. If you decide to have sexual intercourse or oral sex (putting your mouth on a partner's genitals), it’s important to talk with your partner about what you are doing and the risks involved. You could get pregnant or get an infection from sex. Having sex with more than one partner increases these risks. The only way to prevent pregnancy or a sexually transmitted infection 100% of the time is to not have sex.

If you decide to have sex, several types of birth control methods can help prevent pregnancy. Birth control methods that use hormones, like birth control pills, patches, or shots, have to be started before you have sex for the first time. Latex condoms are a form of birth control that helps prevent pregnancy and also protects you from some infections.

Who can I talk to about these changes?

Try talking to your parents or other adults about your questions or concerns. Parents can be your best resource and strongest support, but you may feel distanced from them and uncomfortable talking with them. Your parents may feel the same way. Remember that your culture, music, and clothing styles are different from what your parents are used to. Your parents may not seem to be in touch with your world, but they really want to know what you are feeling and going through. Be open when they ask you about things like sex, drugs, and friendships. If you feel like your parents don’t understand your needs, talk to them about it and ask them if you can spend more time together. You may also be able to talk with your healthcare provider, a trusted relative, friend, or teacher about the changes you are going through.

Developed by RelayHealth.
Pediatric Advisor 2013.2 published by RelayHealth.
Last modified: 2012-11-28
Last reviewed: 2012-04-12
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
© 2013 RelayHealth and/or its affiliates. All rights reserved.
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