Puberty Growth Spurt: Hormonal Drivers and Influencing Factors

Hormonal Orchestration

• Growth hormone (GH): Pituitary surge → chondrocyte/osteoblast proliferation → long-bone elongation.
• Sex steroids:
  • Testosterone (boys): ↑ protein synthesis, muscle, bone width, height velocity.
  • Estrogen (girls): Earlier, shorter peak; epiphyseal fusion ends growth sooner.

Modifying Factors

• Genetics (parental height)
• Nutrition (protein, Ca, Vit D, Zn)
• Sleep (GH pulses in deep sleep)
• Chronic illness, endocrine disorders

Girls typically peak ~11–12 yr; boys ~13–14 yr. Timing and magnitude vary widely.