Growing up

Teenagers talk about their experience of growing up and how they cope with the changes in their bodies.

Media last reviewed: 07/01/2013

Next review due: 07/01/2015

Girls and puberty

What happens to girls' bodies during puberty. Includes growing hair, breasts, periods and moods

Puberty describes the time in life when the body matures sexually and the reproductive organs become functional. It is caused by a release of the sex hormones testosterone and oestrodiol in the body.

Puberty causes:

  • physical changes – including rapid growth spurts, the development of breasts in girls and an increase in penis size in boys
  • psychological changes – these can cause teenagers to become moody, self-conscious and aggressive
  • behavioural changes – these can cause some teenagers to experiment with new and potentially risky activities, such as smoking, drinking, alcohol and sex

Read more detailed information about the symptoms of puberty and the causes of puberty

When does puberty start?

There is no set age for puberty to start. The age at which puberty begins and the rate of development differs from child to child.

Most girls will begin puberty at 8-14 years of age, with the average age being 11. Girls develop more quickly than boys. Most girls reach full sexual maturity within four years of beginning puberty.

Boys tend to develop later than girls, and the development process usually takes longer. Most boys begin puberty at 9-14 years of age, with the average age being 12. Most boys reach maturity within six years of beginning puberty.

Early or delayed puberty

If a child experiences puberty earlier or later than normal, this is known as early (precocious) puberty, or delayed puberty.

In some cases this may be caused by an underlying condition. If there is no obvious cause, such as a long-term illness, then tests may be needed to help diagnose any problems.

Read more information about the complications of puberty.

Page last reviewed: 11/06/2012

Next review due: 11/06/2014


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