Puberty is defined as the onset of secondary sexual features due to the activation and maturation of the hormone systems and glands related to adult sexual function and fertility.

Puberty can be early (precocious) or delayed. Typically girls should not show signs of puberty before 8 years of age and boys should not show signs of puberty before 9 years of age. These signs include development of breast buds, enlargement of the testes or penis, pubic hair growth or development of adult body odour and acne.

Girls should develop breast by 12 years of age and boys should show some signs of puberty by 14 years of age.

Both early and delayed puberty may be abnormal and deserve further investigation.

Precocious puberty

Premature thelarche

Premature adrenarche

Premature menarche

Central or peripheral precocious puberty

Delayed puberty

Klinefelter syndrome

Turner syndrome