mwapShannon flew into the house at top speed, climbing the stairs two at a time to reach her big sister’s bedroom. She entered the room, closed the door behind her, leaned aginst it, and pronounced in a hushed. reverent voice, “I just got my period. Now what do I do?”

“What do you mean, what do you do?”

“I mean, what if I bleed all over my clothes and everybody knows about it? God, Jenny, I’m scared.”

Jenny got off the bed, went to Shannon, and put her arms around her. “Hey, Shannon. Come on. It’ll be OK. I felt the same way. I thought all the guys would know about it and laugh. But they didn’t. Nobody every knew, except people that I wanted to know.”

Shann on was quite for a minute. “Jenny, I’m just not sure how to manage all this stuff about napkins and tampons and–blood–and everthing!”

What Shannon and Jenny are sharing are emotions that surround menarche (men-ar-kee), the term for the first menstrual period. Most girls go through a mixture of embarrassment, apprehension, and excitement at the start of their first menstrual period.

Understanding the basics of menstruation can often go a long way toward relieving the anxiety that surrounds the beginning of your monthly cycle. Here are some basics:

Before Menarche

The body’s preparation for menarche begins as part of overall sexual development, starting around the age of 11. But in some girls it can begin much earlier; in others, much later.

Among the early signs of development are an increase in body hair, the beginnings of breasts, and a change in body shape, including fuller hips. Most girls go through a growth spurt right before menarche, during whichi they add several inches to their height along with several pounds to their weight.

Their sweat glands become more active, and a normal body odor develops as a result of an increase in sex hormones. Their skin often becomes more oily, sometimes triggering acne and other skin problems. A girl’s body is getting ready on the inside, as the uterus and vagina grow. When her body reaches the stage of pelvic development to bear children, it’s time for menarche.

A first menstrual period signified that a girl has become mature enough physically to nurture a future baby. She can become pregnant.

While a first period can occur anytime between 9 and 16, the average age of menarche is between a girl’s 12th and 13th birthdays.

Delayed Menarche

Not all girls begin their period by age 13. Several factors can delay the onset of menstruation. Among them are poor nutrition, emotional stress, and excessive exercise.

Girle show are undernourished are more likely to be late in starting to menstruate. Examples include famine victims, those who diet excessively, and girls who haves anorexia (an eating disorder).

Menarche can also be delayed by two or three years for athletes, dancers, and others who consistently exercise intensively and have a high-energy output. This is most likely when atheltic or dance training begins well before age 13.

On the other hand, prolonged emotional stress during childhood may cause an early menarche. Young girls in families where there is a lot of stress are more likely to begin menstruation between ages 9 and 11. However, a family history of an early menarche may also be a reason.

Menstruation Facts and Myths

During menstruation, levels of estrogen, made by the ovaries, start to rise and make the lining of the uterus grow and thicken. In the meantime, an egg (ovum) is one the ovaries starts to mature. It is encased in a sac, which continues to produce estrogen as the egg grows.

At about day 14 of a typical 28-day cycle, the sac bursts and the egg leaves the ovary, traveling through one of the fallopian tubes to the uterus. The release of the egg from the ovary is called ovulation. Some women konw whey they’re ovulating, because at midcycle they have som pain–typically a dull ache on eitehr side of the lower abdomen lasting a few hours. Some women also have very light bleeding, or spotting, during ovulation.

After the egg is expelled, the sac remains in the ovary, where it starts producing mainly progesterone. The rising levels of both estrogen and progesterone help build up the uterine lining to prepare for pregnancy.

The few days before, during, and after ovulation are a woman’s “fertile period”–the time when she can become pregnant. Because the length of menstrual cycles vary, many woman ovulate earlier or later than day 14. It’s even possible for a woman to ovulate while she still has her period if that month’s cycle is very short.

What’s Normal?

Some girls are unsure of how much bleeding to expect each month. “The amount of bleeding varies from woman to woman because everybody’s body has a different way of building up the lining of the uterus,” says Lisa Rarick, M.D. “A lighter flow or heavier flow doesn’t mean you can’t get pregnant as easily or you’re never going to get pregnant, or that your periods will alwaus stay the same way. But if you’re bleeding excessively–soaking one or more tampons or pads an hour–you should see a doctor to see if there’s a problem.”

Rarick, a gynecologist with FDA’s Center for Drug Evaluation and Research, says teenagers often are concerned if they expel blood clots during their periods. She says this is not dangerous; they are clumps of pooled blood in the vagina. Sometimes, instead of flowing freely, blood drains from the uterus and stays in the vagina until there’s a change in position–say, from sitting to standing.

Many girls are surprised by variations in the color of menstrual bloos, which ranges from bright red to dark brown, depending on the point in their menstrual cycle. A menstrual period can last anywhere from thre to six days; most girls and women have menstrual cycles that range from 25 to 31 days apart, and often the duration varies in length from month to month.

Learning how to cope with sanitary napkins and tampons can be confusing at first. Sanitary pads or tampons, which are mafe of cotton or another absorbent material, are worn to absorb the blood flow. Sanitary pads are placed inside the panties; tampons are insterted into the vagina.

Girls who use tampons should be aware of toxic shock syndrome, or TSS, a rare but serious–and sometimes fatal–disease that’s been associated with tampon use. Tampon packages carry information about TSS on the box or inside. Because TSS mostly affects 15- to 19-year-olds, it’s especially important for teenagers to know what signs to look for. If you develop the following symptoms while menstruating, remove the tampon and get medical help right away:

* sudden fever over 102 degrees Farenheit * vomiting * diarrhea * dizziness, faingint, or near fainting when standing up * a rash that looks like sunburn.

It’s estimated that at least half of all girsl and women occasionally experience mesntrual cramps, Some have them regularly arouynd the time of menstruation. For 5 percent to 10 percent of these, their pain is so severe it may disable them anywhere from two hours to two days a month. In fact, menstrual cramps are cited as a common cause of lost school or work days among young women.

In many cases, nonprescription medications such as ibuprofen, used only as directed, can relieve the pain of menstrual cramps and treat some of the accompanying symptomns, such as tension, irritability, and water retention.

If the pain of menstrual cramps interferes with your life, it may be a good idea to consult a doctor.

Menopause: A Second Rite of Passage

Starting around age 50, most women begin menopause, the third phase of their body’s menstrual life cycle. Menopause is the ending of menstrual periods at a time when, for most women, a third of their life lies ahead.

Many women are relieved to be free of the concerns of monthly bleeding yet troubled about the possible side effects of menopause, including hot flashes and weight gain. Many women worry that menopause signals the loss of youth and changed body.

Menopause typically takes place between 48 and 52, and as it approaches, manu women notice a change to irregular menstrual periods–longer or shorter, more or less often; in some cases, they may begin skipping periods entirely. Bleeding patterns may change, and the flow may increase or decrease.

Hot flashes are experienced by about three-quarters of menopausal women. A hot flash is a sensation of intense heat that comes on suddenly, with no warning. A woman’s skin may also become flushed, and she may begin to sweat heavily. Some women are awakened from sleep by hot flashes. Most hot flashes last about three minutes and mainly affect the head, neck, and shoulders,

Weight gain need not be a side effect of menopause. Careful attention to nutrition and a program of regular exercise can help women maintain a healthy body weight and a sense of control.

After a few years of menopause, women are free of the possibility of pregnancy. However, “caboose” or menopausal babies do happen. It’s therefore important that safe sex be practiced to avoid both pregnancy and a sexually transmitted disease.

Virtually every older woman has gone through both menarche and menopause. Both are vital parts of women’s development. Treating your body with care, understanding, and respect can go a long way toward creating comfort with menarche and all the way through to menopause and the years beyond.