WebMD Feature

By Camille Peri

Reviewed by Brunilda Nazario, MD

Making Your Body Work for You

“Am I normal?” That's a question many girls ask during puberty. Chances are your body development is quite normal. But there’s so much going on at once, just knowing what's coming can help put your mind at ease. Here's what to expect during puberty -- and why.

Intro to Puberty

Puberty usually starts between the ages of 8 and 13 and lasts a few years. It may start earlier in girls who are overweight, or later in girls who are very athletic or thin. If you are 12 and haven't started developing breasts or are 15 and haven't gotten your period, your doctor will probably want to examine you to make sure everything's OK.

During puberty, your body releases hormones that stimulate your ovaries to start producing the female hormone estrogen. Gradually, a girl's body starts changing into a woman's body. But these surging hormones can also make your mood go up and down -- and sometimes it may seem as if your body is out of control.

Growing and Gaining Weight

Most girls experience growth spurts early in puberty, while most boys have them later in puberty. That’s why many girls are taller than boys in middle school.

Increased body fat is also a normal part of puberty. “You may go from 8% to 21% body fat,” says Kathy McCoy, MD, a psychiatrist who co-wrote The Teenage Body Book and who was a columnist for Seventeen magazine.

Don’t go on a diet to try to lose this weight. "It’s not bad fat," says Melisa Holmes, MD, who co-wrote the Girlology book series. "Women just have to have a certain amount of body fat for reproduction and the health of our menstrual cycles.”

Breast Development

Along with gaining curvier hips, your breasts grow during puberty. Inside them, a network of milk ducts develops. This is your body's way of preparing you to nurse a baby when you're older.

Breast development is one of the changes that stress girls out the most. Many girls worry that their breasts aren’t growing enough. But breasts usually continue to grow until you’re 17 or 18 years old -- or even into your 20s. Sometimes one breast grows faster than the other, although the slower one usually catches up.

Your nipples also change during puberty. They can become pink or dark brown, turned inward or out. Sometimes hairs grow around them. All of this is normal.

If you want to get an idea about what your breasts might look like as a woman, look at your mom. Your final breast size is based partly on heredity. “Your breasts aren’t necessarily going to be the same as your mom’s because you’ve got your dad’s genes added in, but you can look back at your ancestors and get a pretty good feel for it,” Holmes says.

Menstruation

Two years or so after your breasts start to develop, you'll probably get your first period. Periods usually last between two and eight days and come every 21 to 35 days. A 28-day cycle is common, but often it takes a while before your periods are regular.

Each month, the lining of your uterus thickens with blood to help a fertilized egg grow. When you don't become pregnant, that lining sheds, and blood comes out of your vagina. Only a couple of tablespoons of blood are released during your period, but it can seem like a lot more.

Vaginal Discharge

You may notice white, sticky stuff in your underpants. That's the fluid that keeps your vagina moist and clean. Vaginal discharge may become thicker and stickier at some points during your menstrual cycle. It has a slight odor but most people can't smell it. Bathing regularly with soap can help reduce the odor if it bothers you.

If your vaginal discharge becomes itchy or irritated, has a strong odor, or is dark yellow or greenish, you may have a vaginal infection. See your doctor.

Body Hair

Puberty brings hair to your body in new places: under your arms, in your genital area, and maybe even on your upper lip. The hair on your arms and legs may also get darker or thicker.

Pubic hair usually starts with a few straight strands and becomes curlier and darker as it grows. Eventually it grows into a thick triangle over the pubic bone and spreads a little to your inner thighs. This growth may start at the beginning of puberty or any time during it.

If you grow hair on your chest or chin, though, see your doctor. You may have a hormone imbalance that needs to be corrected.

Sweating Through Puberty

Your body starts sweating more during puberty. When sweat combines with bacteria -- under your arms, for instance -- it causes body odor. To control odor, bathe or shower every day with a deodorant soap and use an antiperspirant. "The higher the aluminum chloride content, the more antiperspirant activity it will have," says obstetrician-gynecologist Holmes. (If you develop a rash under your arms, you may be allergic to aluminum and should use an antiperspirant that doesn’t contain it.) Also, clothes made of fabrics that wick moisture will dry faster and don't show armpit stains as much.

Your feet may get sweaty too. Wear cotton socks to absorb moisture, and rotate your shoes, so they have time to dry out. Avoid shoes made of plastic, rubber, or other manmade materials. If you have sweaty palms, skip hand lotion. Use a hand sanitizer to keep your hands drier.

Acne

Acne -- whiteheads, blackheads, and pimples -- is caused by surging hormones. If you have it, try cleansing with a gentle non-soap cleanser and use over-the-counter acne products with benzoyl peroxide or salicylic acid. It also helps to use sunscreens, moisturizers, and makeup that are labeled “oil free” or “non-comedogenic.” If these things don’t get your acne under control, a dermatologist can use other treatments that will help.

Making Your Body Work for You

At some point during puberty, you will probably look at your face, hair, or body in the mirror and not like what you see. At those times, Holmes says, it can help to appreciate the great things your body can do -- like playing the piano, doing a back flip, or climbing a mountain. If you hate your body most of the time, talk to a school nurse or counselor who can help you learn to see your body differently.

SOURCES:

Melisa Holmes, MD, obstetrician-gynecologist, Greenville, S.C.; coauthor, Girlology book series, Health Communications, Inc.

Kidshealth: “Everything You Wanted to Know About Puberty.”

Kathleen McCoy, MD, psychotherapist, Florence, Ariz.; coauthor, The Teenage Body Book, Hatherleigh, 2008.

Medline Plus: “In Young Girls, Obesity Linked to Early Puberty, Analysis Reveals.”

Pfiefer, K. American Medical Association Girl’s Guide to Becoming a Teen, Jossey-Bass, 2006.

American Academy of Dermatology (AAD): “Acne,” “Food Does Not Cause Acne.”

Amy Wechsler, MD, dermatologist and psychiatrist, New York; assistant clinical professor of dermatology, SUNY Downstate Medical College, Brooklyn; adjunct assistant clinical professor of psychiatry, Weill Cornell Medical College, New York; N.Y.

WebMD Feature: “Obesity and Early Puberty: What's the Risk?”

Reviewed by Brunilda Nazario, MD on August 12, 2011

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