Your daughter's breasts are budding beneath what used to look like an innocent little tank top. Your son comes home from soccer practice smelling like a guy who's been digging on a road crew all day. What's going on here?

Welcome to puberty, that time in life when kids sprout up, fill out, and maybe even mouth off.

Puberty was awkward enough when you were the one going through it. So how can you help your child through all the changes?

Stages of Puberty

Sure, most of us know the telltale signs of puberty - hair growth in new places, menstruation, body odor, lower voice in boys, breast growth in girls, etc. But we may not fully comprehend the science behind all of these changes. Here's a quick look at how it works.

At some point, usually not until after a girl's 8th birthday or after a boy turns 9 or 10, puberty begins when an area of the brain called the hypothalamus starts to release gonadotropin-releasing hormone (GnRH). When GnRH travels to the pituitary gland (a small gland under the brain that produces hormones that control other glands throughout the body), it releases two more puberty hormones - luteinizing hormone (LH) and follicle-stimulating hormone (FSH).

What happens next depends on a child's gender. For boys, the hormones travel through the bloodstream to the testes (testicles) and give the signal to begin production of sperm and the hormone testosterone. In girls, the hormones go to the ovaries (the two oval-shaped organs that lie to the right and left of the uterus) and trigger the maturation and release of eggs and the production of the hormone estrogen, which matures a female's body and prepares her for pregnancy.

At about the same time, the adrenal glands of both boys and girls begin to produce a group of hormones called adrenal androgens. These hormones stimulate the growth of pubic and underarm hair in both sexes.

For a Boy

The physical changes of puberty for a boy usually start with enlargement of the testicles and sprouting of pubic hair, followed by a growth spurt between ages 10 and 16 - on average 1 to 2 years later than when girls start. His arms, legs, hands, and feet also grow faster than the rest of his body. His body shape will begin to change as his shoulders broaden and he gains weight and muscle.

A boy may become concerned if he notices tenderness or swelling under his nipples. This temporary development of breast tissue is called gynecomastia and it happens to about 50% of boys during puberty. But it usually disappears within 6 months or so.

And that first crack in the voice is a sign that his voice is changing and will become deeper.

Dark, coarse, curly hair will also sprout just above his penis and on his scrotum, and later under his arms and in the beard area. His penis and testes will get larger, and erections, which a boy begins experiencing as an infant, will become more frequent. Ejaculation - the release of sperm-containing semen - will also occur.

Many boys become concerned about their penis size. A boy may need reassurance, particularly if he tends to be a later developer and he compares himself to boys who are further along in puberty. If a boy is circumcised, he may also have questions about the skin that covers the tip of an uncircumcised penis.

For a Girl

Puberty generally starts earlier for a girl, some time between 8 and 13 years of age. For most girls, the first evidence of puberty is breast development, but it may be the growth of pubic hair in some. As her breasts start to grow, a girl will initially have small, firm, tender lumps (called buds) under one or both nipples; the breast tissue will get larger and become less firm in texture over the next year or two. Dark, coarse, curly hair will appear on her labia (the folds of skin surrounding the vagina), and later, similar hair will begin growing under her arms.

The first signs of puberty are followed 1 or 2 years later by a noticeable growth spurt. Her body will begin to build up fat, particularly in the breasts and around her hips and thighs, as she takes on the contours of a woman. Her arms, legs, hands, and feet will also get bigger.

The culminating event will be the arrival of menarche, her first period (also called menstruation). Depending on the age at which they begin their pubertal development, girls may get their first period between the ages of 9 and 16.

Common Puberty Concerns

The term puberty is generally used to refer to the specific physical changes kids experience as they move toward adulthood, but that doesn't mean that these bodily changes are without emotional consequences.

Some girls are excited about their budding breasts and new training bras; others may worry that all eyes are focused on their breasts. Some boys love the sight of themselves all lathered up with shaving cream; others may be uncomfortable with the attention they get for a few new shoots of hair.

Pimples are common for most teens. Acne is caused by glands in the skin that produce a natural oil called sebum. Puberty hormones make the glands produce extra sebum, which can clog the pores. Washing gently with water and mild soap can get rid of excess sebum and help reduce breakouts. In more severe cases of acne, there are several helpful over-the-counter and prescription medications available. You might talk to your child's doctor about recommending a dermatologist (a doctor specializing in skin) if basic skin care and over-the-counter medications aren’t keeping things under control.

Kids who once associated bath time with play need to learn to wash frequently enough and to apply deodorant or antiperspirant. A teen who's learning to use a razor will need instructions on how to keep it clean, to throw a disposable one away before it becomes dull and ineffective, and to not share it with others.

Boys, capable of having an erection since infancy, can now experience ejaculation. The first ejaculation usually occurs between the ages of 11 and 15, either spontaneously in connection with sexual fantasies, during masturbation, or as a nocturnal emission (also called a wet dream). If he doesn't know about wet dreams before he has one, a boy may think he has urinated accidentally or that something has gone wrong with his body.

As children mature physically and emotionally, they become increasingly curious about their sexuality and their own bodies. Although infants and younger children do touch their own genitals from time to time because they like the way it feels, masturbation is more common in older children, from the preadolescent and teen years and beyond.

There are lots of myths and beliefs about masturbation. No ... it won't cause your child to grow hair on his hands, become infertile, go blind, or develop new emotional problems. A small number of children and teens with already existing emotional problems may become preoccupied with masturbation - just as they may become overly occupied with other behaviors or thoughts. Constant or obsessive masturbation may be a sign of anxiety or other emotional problem. But, other than that, masturbation is generally considered by doctors to be a common form of normal sexual self-exploration. Although some preteens and teens may choose to masturbate, others may not.

Because masturbation is often considered a private topic, many children may feel too embarrassed to talk about it because they're concerned that their parents will be angry or disappointed with them. Some kids may prefer to talk to older siblings, friends, or their doctors than a parent. If you continue to be concerned or have questions about masturbation, talk with your child's doctor.

Talking to Your Child About Puberty

Boys and girls can see these changes happening to each other - in some cases, they can smell them. It's important to talk to your child about how bodies change - sooner, rather than later.

Be prepared to talk to a girl about the expected events of puberty, including menstruation, when you see the first signs of breast development, or earlier if she seems ready or has questions. A boy should know about normal penile development, erections, and nocturnal emissions before age 12 - sooner, if he's an early developer. And it's also important to talk to your child about what's happening to members of the opposite sex.

It's best not to have "The Talk" but rather a series of talks, ideally beginning when your child is young and starting to ask questions about body parts. Each time you talk, offer more and more detail, depending upon your child's maturity level and interest in the topic.

And, if your child has a question, answer it right away. If you feel uncomfortable or uncertain about having these discussions with your child, ask your child's doctor for advice.

Reviewed by: Steven Dowshen, MD
Date reviewed: November 2007