As an adult, you probably remember puberty as feeling awkward in your skin while your body went through lots of changes. Or maybe you blocked it out altogether.

Now you’re a parent whose child is experiencing these changes and things are a little different. You want to know what to expect, so you can help your child through each stage of development.

Professor James M. Tanner, a child development expert, was the first to identify the stages of puberty and put them into five categories. Today these stages are known as the Tanner stages. While each person’s puberty timetable may be different, these stages outline a general guide to development.

Here are the Tanner stages and what you can expect to see in boys and girls during each stage.

Tanner Stage One

In this first stage, the brain is just starting to send signals to the body to prepare for changes. The hypothalamus begins to release gonadotropin-releasing hormone (GnRH). It travels to the small area under the brain that makes hormones that control other glands in the body (pituitary gland). Two more puberty hormones, called luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are produced.

These early signals typically start after a girl’s 8th birthday and after a boy’s 9th or 10th birthday.

There aren’t any noticeable physical changes for boys or girls at this stage.

Tanner Stage Two

Stage two marks the beginning of physical development. Hormones begin to send signals throughout the body.


African-American girls usually start puberty a year before Caucasian girls, and are ahead when it comes to breast development and having their first period.

  • It usually starts around age 9 to 11.
  • First signs of breasts, called “buds,” start to form under the nipple. They may be itchy or tender, which is normal.
  • It’s common for breasts to be different sizes and grow at different rates, so you shouldn’t be worried if one “bud” appears larger than the other.
  • The darker area around the nipple (areola) will expand.
  • The uterus begins to get larger.
  • Growth in height can range from 2 to 3.5 inches.
  • Small amounts of pubic hair start growing on the lips of the vagina.


  • Usually starts around age 11.
  • The testicles and skin around the testicles (scrotum) begin to get bigger.
  • Early stages of pubic hair forms on the base of the penis.

Tanner Stage Three

Physical changes are becoming more obvious.


  • Usually starts after age 12.
  • Breast “buds” continue to grow and expand.
  • Pubic hair gets thicker and curlier.
  • Hair starts forming under the armpits.
  • First signs of acne may appear on face and back.
  • Highest growth rate for height begins at around 3.2 inches per year.
  • Hips and thighs start to build up fat for a curvier womanly shape.


  • Usually starts around age 13.
  • Penis gets longer as testicles continue to grow bigger.
  • Some breast tissue may start to form under the nipples (this happens to some teenage boys during development and usually goes away within a couple of years).
  • Boys begin to have wet dreams (ejaculation at night).
  • As the voice begins to change, it may “crack,” going from high to lower pitches.
  • Muscles get larger.
  • Height growth increases to 2 to 3.2 inches per year.

Tanner Stage Four

Puberty is in full swing and both boys and girls are noticing many changes.


  • Usually starts around age 13.
  • Breasts are filling out from “buds” to look shapelier.
  • Many girls get their first period, typical age is from 12 to 14, but it can happen earlier.
  • Height growth will slow down to about 2 to 3 inches per year.
  • Pubic hair gets even thicker.


  • Usually starts around age 14.
  • Testicles, penis, and scrotum continue to get bigger and the scrotum will get darker in color.
  • Armpit hair starts to grow.
  • Deeper voice becomes permanent.
  • Acne may start to appear.

Tanner Stage Five

This final phase marks the end of your child’s physical maturation.


  • Usually happens a little after age 14.
  • Breasts reach adult size and shape.
  • Periods become regular after six months to two years.
  • Girls reach adult height one to two years after their first period.
  • Pubic hair fills out to reach the inner thighs.
  • Reproductive organs and genitals are fully developed.
  • Hips, thighs, and butt fill out in shape.


  • Usually starts around age 15.
  • Penis, testicles, and scrotum will have reached adult size.
  • Pubic hair has filled in and spread to the inner thighs.
  • Facial hair will start coming in and some boys will need to begin shaving.
  • Growth in height will slow down, but muscles may still be growing.
  • By age 18 most boys have reached full growth.


Acne can be a problem for both boys and girls. The changing hormones that cause oils to build up on the skin, clogging pores, trigger it. Your child can develop acne on the face, back, or chest. Some people have a worse experience with acne than others. If you have a family history of acne issues, there is a higher possibility your child will struggle with it as well.

Generally, acne can be treated by washing the areas regularly with a mild soap. There are also over-the-counter creams and ointments to help control breakouts.

For mild to more severe acne, you may consider taking your child to see a dermatologist. The doctor can recommend stronger prescription treatments.

Body Odor

Larger sweat glands also develop during puberty. To avoid any embarrassment from unpleasant body odor, talk to your child about deodorant options and make sure they shower regularly, especially after intense physical activity.

What You Can Do

Puberty can be frustrating for kids and parents. In addition to the many physical changes, hormones are also causing emotional changes. You may notice your child being moody, behaving differently, or talking back more than usual.

It’s important to react with patience and understanding. We’ve all been through puberty, and we know it isn’t easy. Your child may be feeling insecure about their bodily changes, including acne. Talk about the changes their bodies are going through and reassure them it’s a normal part of maturing. If something is particularly troubling, talk to your child’s doctor as well.