puberty in boys
Last reviewed 04/2023
In boys the onset of puberty is between 9.5 and 13.5 years (in 95%) and is completed by the ages 15-17 years. It is predominantly under the control of growth hormone and androgens.
The normal process of puberty in boys with the development of secondary sexual characteristics is as follows:
- first sign is the enlargement of the testes and scrotum
- reddening / rugosity of the scrotal skin
- development of pubic hair
- penile growth (length then width)
- initiation of spermatogenesis
- growth of axillary hair
- growth of facial hair
- voice breaks: the result of laryngeal growth and lengthening of vocal cords
Peak growth rate occurs between the ages of 12-17 years. Testosterone inhibits the growth spurt by fusing of the epiphyses.