Overview
Puberty is when a child’s body begins to develop and change as they become an adult. In general:
- Boys start puberty between the ages of 9-14 years old
- Girls start puberty between the ages of 8-13 years old
Puberty is initiated by increasing the frequency and amplitude of pulses of gonadotropin-releasing hormone (GnRH) which leads to the production of luteinising hormone (LH) and follicle-stimulating hormone (FSH) and testosterone or oestrogen.
Puberty in Girls
Overview
Key points include:
- Breast enlargement is generally the first sign of puberty
- This may be unilateral
- Menarche usually starts between 11-15 years old
- In general, it occurs 2-3 years after the start of breast development
- The growth spurt is maximal before menarche at around 11-12 years old
The stages of puberty in girls can be measured using the Tanner staging system which assesses breast development, pubic hair, and growth.
Puberty in Boys
Overview
Key points include:
- The first sign of puberty is testicular enlargement around 12-13 years old
- A testicular size of ≥4 mL indicates the onset of puberty
- Penile growth, scrotum reddening and thickening, and pubic hair growth follow 1-2 years after testicular enlargement
- Many boys may develop gynaecomastia
The stages of puberty in boys can be measured using the Tanner staging system which assesses genitalia, pubic hair, and growth.
