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Early or delayed puberty

Puberty is when a child's body begins to develop and change as they become an adult.

Signs of puberty include girls developing breasts and starting periods, and boys developing a larger penis and testicles, a deeper voice and a more muscular appearance.

The average age for girls to start puberty is 11, while for boys the average age is 12.

But it's perfectly normal for puberty to begin at any point between the ages of 8 and 13 in girls and 9 and 14 in boys.

There's not usually any need to worry if puberty does not start around the average age, but it's a good idea to speak to your GP for advice if it starts before 8 or has not started by around 14.

In some cases, early puberty or delayed puberty could be a sign of an underlying condition that may need to be treated.

Early puberty

Early puberty, also called precocious puberty, is when:

Some girls and boys may develop certain signs of puberty at a young age, but not others.

For example, girls may start periods before the age of 8 but have no breast development.

See your GP if this happens to your child.

Causes of early puberty

It's not always clear what causes early puberty. It may just be a tendency that runs in your family.

Occasionally it can be caused by:

Early puberty mostly affects girls and often has no obvious cause. It's less common in boys and may be more likely to be associated with an underlying problem.

Tests and treatments for early puberty

Your GP may refer you to a specialist if they think there could be an underlying cause that needs to be investigated.

Tests that may be carried out include:

Early puberty can be treated by:

Treatment with medication is usually only recommended if it's thought early puberty will cause emotional or physical problems, such as a very short stature or early periods in girls, which may cause significant distress.

Delayed puberty

Delayed puberty is when:

Causes of delayed puberty

It's not always clear what causes delayed puberty. It may just be a tendency that runs in your family. Delayed puberty is generally more common in boys.

Occasionally it can be caused by:

Tests and treatments for delayed puberty

Your GP may refer you to a specialist if they think there could be an underlying cause of delayed puberty that needs to be investigated.

Tests that may be carried out include a blood test to check hormone levels, a hand X-ray to help determine likely adult height, and an ultrasound or MRI scan to check for problems with glands or organs.

Delayed puberty can be treated by:

Treatment with medication is usually recommended if the lack of development is causing problems, such as significant distress.