Which secondary sexual characteristics commonly develop in boys during puberty?

During puberty, boys develop several secondary sexual characteristics driven by the increased production of testosterone by the testes. These physical features, which emerge as a child transitions toward sexual maturity, include the following:12

• Hair Growth: Pubic hair typically appears first, followed by the development of axillary (armpit) and facial hair. Over time, hair may also grow on the chest, abdomen, and limbs, while the hairline at the temples may recede.1342
• Voice Changes: The larynx enlarges and the vocal cords lengthen, causing the voice to deepen.14
• Body Composition and Growth: Boys experience a rapid increase in height and weight, along with a significant increase in muscle mass and strength.542
• Skin and Glandular Changes: Skin glands, particularly apocrine sweat glands, become more active. Additionally, the scrotal skin may become reddened and wrinkled.412
• Other Changes: Some boys may experience transient breast enlargement, known as gynecomastia, and skeletal features such as the pelvic bones and skull may become more accentuated.42

These changes are distinct from primary sex characters, such as the penis and testes, which are present at birth.3