One day, something very new will happen to you. There may be signs to tell you when it's about to happen. But no one can tell you what day it will happen. Or if it will happen in the morning or at night. Or if you'll be asleep or awake. It happens to every healthy girl in the world. One day, maybe soon, you will begin to bleed from your vagina. It will be your period — the first of many you will have in the course of your life.

Having your period is also called menstruation. It's a sign that you're growing up. It means that your body is healthy and normal. This booklet will tell you what it's all about. Share it with your friends and parents.

What's happening to me?

Bodies don't all grow at the same rate. All of these young women will be 13 in three months.
Your body is changing into a woman's body when you start having your period. The changes may begin when you're nine. Or they may not begin until you are twelve, thirteen, or older. These changes will end when your body is completely adult.

You can see some of the changes. Your breasts will get bigger. Your hips will get wider. Hair will begin to grow under your arms and around your vulva.

Only girls have vulvas. The labia, clitoris, urethra, and the opening of the vagina are all part of your vulva. The drawing of the vulva shows you where these parts are. You can use a mirror to look at your own vulva.

You can use a mirror to look at your own vulva.

There are other changes that happen inside your body. These changes will make it possible for you to get pregnant and have a baby.

The parts of your body that can make a baby are inside you. They are called reproductive organs. They grow up just like the rest of your body. These parts are the vagina, cervix, uterus, fallopian tubes, and ovaries. Your vagina connects your vulva to the reproductive organs inside your body. Look at the drawing of the reproductive organs to see how these parts fit together. Your period will begin when these parts have grown up.

Sometimes a girl's reproductive organs grow up before she does. That's why she can become pregnant if a boy puts his penis in or near her vagina — even if she's not all grown up.

How does my reproductive system work?

Girls have two ovaries. Each one holds hundreds of thousands of very tiny eggs. The eggs are so tiny that you can only see them with a microscope. Girls are born with all the eggs they will ever have. An ovary releases one egg about once a month. This is called ovulation.

The egg moves through a tube toward the uterus. Most of the time, the egg breaks apart before it gets to the uterus. But that doesn't always happen. If a sperm from a boy's penis meets the egg on its way to the uterus, they can join together. The joining of an egg and a sperm is called fertilization. Pregnancy begins if a fertilized egg attaches itself to the lining of the uterus.

Before the egg is let go, the uterus begins building up a lining. It is made of tissue and blood like almost everything else inside us. The lining is like a nest for the egg if pregnancy happens. If it doesn't happen, the egg breaks apart, and the lining of tissue and blood isn't needed. It flows out of your uterus, through your cervix, through your vagina, and out of your body. This is called menstrual flow. You will be having your period when this happens to you.

There are usually 14–16 days from ovulation to the beginning of a girl's period. But the time from the beginning of the period to the next ovulation may vary. It may be less than one week. It may be two weeks or more.

The time from the first day of one period to the first day of the next is called a menstrual cycle. Your menstrual cycles will likely go on until you are 45 to 55 years old.

Sometimes a girl will have some spotting of blood for a day or two after ovulation. This is normal, but it is not her period.

What is menarche?

Menarche (men-NAR-key) is the time of your first period. Some families celebrate menarche as the time when a girl becomes a woman. Sometimes parties, gifts, and congratulations celebrate a young woman's first period. Other families are more private about menarche. But whether or not menarche is celebrated in your family, it is an exciting and important moment in your life.

How long will my period last?

Periods usually last from three to seven days. The flow usually starts light. It can get heavy for two or three days, then get light again until it stops. It often starts off a rusty color, then gets redder. It lightens to a rust color again until it stops.

How often will I have my period?

You will have a period about once a month. A normal menstrual cycle can be as short as 21 days or longer than 35 days. Changes from month to month are also normal. Some months you may have no period, especially during the first year or two. Your health can make a difference. Too much exercise or very strict dieting, for example, can use up all your body fat. You might not have periods if that happens. Stress can make a difference, too.

Most girls and women don't feel ovulation when it happens. They don't know for sure when it actually occurs. They may feel some pain in the lower abdomen. Ovulation takes place around the middle of each menstrual cycle. Many girls mark a calendar with an X on the days they bleed. For most women, periods will happen every 25–30 days.

Keeping a calendar will help you predict when you will bleed again. It will help you know when you are going to need sanitary pads or tampons. Also, you'll be able to know if your period is late or early. And you'll have a record if you need to see your clinician about any health problem.

Here are some examples of how you can chart your menstrual cycle on a calendar.

Menstruation Calender

O — Ovulation — the middle of the menstrual cycle: 14 days before the next period

X — Days of Menstruation

[ ] — One Menstrual Cycle — Each begins on the first day of a period and lasts to the beginning of the next period. The first cycle in this calendar is 27 days long. The second cycle is 30 days long. The third cycle is 25 days long.

Will I feel weak when I lose blood during my period?

Probably not. Usually, there are only four to six tablespoonfuls of blood in the whole flow. This is a small amount. The rest is bits of the unused lining and other fluids. By the time your period ends, the flow will have amounted to between half a cup and a full cup of liquid.

Women who have a very heavy flow and change maxi pads or super tampons every few hours should see their clinician. A simple blood test can tell if a heavy period is causing anemia — feeling tired because of a loss of red blood cells. A healthy diet replaces lost blood cells.

How do I keep the flow from staining my clothes?

Most women use either sanitary pads or tampons to absorb the flow. You can buy them in drugstores or supermarkets. Usually, they come in packages of 10 or more. Every package has instructions in it. They come in different sizes and varieties. Some are for lighter flows. Some are for heavier flows. You will need to decide which type of pad or tampon is most comfortable for you.

Most pads stay in place by sticking to the inside of your underwear. Others are pinned to it. Some are held in place by special belts. Others are made especially for teens.

Tampons fit inside the vagina. The walls of the vagina hold them in place. A tampon cannot get lost inside you and move to another part of your body. It stays inside your vagina until you remove it. Each tampon has a string that hangs out of the vagina. Slowly pulling the string removes the tampon easily.

An unpleasant odor will occur if you forget or are unable to remove a tampon for several days. This can cause minor as well as serious infections. You should see your clinician as soon as possible. The tampon can be easily removed.

Using a tampon or pad may seem a little strange at first. Try different types until you decide what you like best. Thinking about the clothes you're going to wear may help you decide. Some girls may feel better using a tampon while exercising or wearing jeans or a bathing suit.

Some girls wonder if tampons will stretch the hymen. The hymen is a thin skin that stretches across the lower part of the opening of the vagina. There is an opening in it to let menstrual flow out of the body. Most girls are born with a hymen.

The hymen is very important to some people. They believe that a girl whose hymen is stretched open is no longer a virgin because she has let a boy put his penis in her vagina. But that isn't always true. Some girls are born without a hymen. Exercise may stretch open the hymen. Tampons may stretch the hymen a little bit. But they don't usually stretch it open all the way. You may prefer to use a pad if you feel it is important not to stretch your hymen.

What do I need to know about tampons and pads?

Here are some tips to make using pads and tampons easier:

  • When you first use a tampon, have someone show you how to correctly place it in your vagina. Ask your mother, older sister, or another woman you trust to help you.
  • Putting a tampon in your vagina shouldn't be painful. But it may hurt if you are not relaxed. Use unscented tampons with soft, tube-shaped applicators when you first begin.
  • Change your tampon or pad every three or four hours to prevent odor, stains on your clothes, and possible vaginal infection.
  • Don't use "high absorbency" tampons throughout your period — check the label for how absorbent the tampon is.
  • Use cold water and soap to remove any stains that get on your clothes.
  • Don't flush pads down the toilet. They'll clog it up. Wrap them in toilet paper and put them in the trash.
  • You can flush tampons but not applicators. Throw applicators away in the trash.
  • Some health care providers advise using pads instead of tampons while you sleep.

Sometimes women who use "high absorbency" tampons all day and night during their periods become ill. This happens when bacteria that are sometimes in the vagina grow too much. This rare illness is called toxic shock syndrome. Stop using tampons if you vomit and have a high fever, diarrhea, and a sunburn-type rash while using one. Tell your parents immediately and see a doctor or clinician right away.

How can I tell if my periods are normal?

You are different from every other girl in the world. Your periods and menstrual cycles will be different, too. What will be normal for you, may not be normal for anyone else. Your cycles may not always last the same number of days when they first begin. Your first few periods may not all be the same either.

It may take a while for your body to get things going smoothly and regularly. You may have a light flow or a heavy flow. Your periods may be late. You may even skip some months. Your period may be late when you get sick. It may be late when you worry about things like taking a test at school. Most likely your periods and cycles will become more regular as you grow older.

How can I tell when my period is coming?

There may be signs. There may not be. For some girls, the signs that their periods are going to start are: tender breasts, feeling tense, and swelling of the abdomen or other parts of the body. Sometimes there's a crampy feeling in the back, legs, or abdomen. Some girls get pimples a few days before. As you get older, you will become more familiar with signs that your period is coming. This will help you be prepared.

What do I do if I get cramps?

Some girls have cramps with their periods. They usually get fewer and fewer cramps with time. Regular exercise may help prevent cramps. Get enough rest. Drink plenty of water. Eat well to help protect against cramps:

  • Avoid salty foods.
  • Have green, leafy vegetables or take 500 mg. of magnesium, each day.
  • Have whole-grain cereals or take vitamin B complex — especially B6, each day.
  • Include a tablespoon of fatty acids — such as cold-pressed olive oil — in your daily diet.

You can use a heating pad on your back or abdomen if you do get cramps. You can buy many kinds of pain relievers for menstrual cramps. Ask your health care provider or pharmacist for information. Talk with a parent or school nurse if heating pads and pain relievers don't help your cramps. It's also a good idea to see a health care clinician. You do not need to suffer with cramps — nurses and doctors can help.

What if my period starts in school?

You can carry a supply of pads or tampons in your bag when you think your period is coming. Ask your school nurse or teacher for them if you forget. Don't be shy. Remember, all women have had periods. Some schools have machines that sell tampons or pads in the girls' bathroom. Public bathrooms often have them, too. If your clothes get stained, you can wrap a sweater around your waist or ask to go home. You can also keep a change of clothes in your gym locker.

Can other people tell when I'm having my period?

No one can tell by looking at you that you have your period. You don't look or act any differently. People will only know you're having your period if you tell them. You can still swim, play tennis, bathe, and do all the things you usually do.

Will I have a period all my life?

Periods stop while women are pregnant. In time, your period will stop for good. Usually, it stops when a woman is between 45 and 55 years old. This is known as "the change of life" or menopause.

Will I have serious problems with my period?

Most girls don't have serious problems. But be sure to tell somebody if you have really bad cramps, if the flow seems very heavy, or if your periods don't become regular. Tell your mother, the school nurse, a teacher you trust, or your family health care provider.

What if I just want to talk about it?

Family members can provide information and support. Share what you know about your period with your girlfriends. You may be surprised how much you know that they don't.

Remember, every healthy adult woman in the world has menstruated. Most of the women you know can answer your questions and will listen to what you want to say. Talk it over with women who make you feel comfortable.

What about the scary stories I hear sometimes?

Don't believe them. For a long time, people didn't understand what having a period was all about. They invented stories about it because they didn't know the facts. A lot of those stories are still around, but they aren't true. Remember:

  • Menstruation is not a "curse" or a "punishment."
  • Losing normal menstrual blood doesn't make you weak.
  • Menstruation doesn't need to put you in a bad mood.
  • Menstruation doesn't mean being "sick" or "unclean."
  • Women can enjoy sex while they have their periods.
  • It is possible to become pregnant before your first period.
  • It is also possible to become pregnant when you are bleeding. It could be spotting after ovulation instead of your period.
  • It is possible to become pregnant from vaginal intercourse during your period.
  • Menstruation has nothing to do with "bad blood."
  • You don't need to stay in bed on the first day of your period.
  • Cold drinks, showers, or baths do not cause menstrual cramps.

The truth is that having your period is a sign that your body is healthy and working the way it should.

For More Information

Your local library is a good place to find the information you need about sex, birth control, and sexually transmitted infections. The Planned Parenthood website for teens,, is also a good resource for sexual health information. Your local Planned Parenthood health center can provide you with information too. For an appointment at the Planned Parenthood health center nearest you, call toll-free 1-800-230-PLAN.

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