On average, the process typically starts between ages 8 and 13 for girls and 9 and 14 for boys. Physiology, Puberty - StatPearls - NCBI Bookshelf
The entire symphony of puberty is directed by the brain. It begins in the hypothalamus, a small region at the base of the brain that acts as the body’s master thermostat. Around ages 8 to 13 (on average), the hypothalamus starts pulsing out a hormone called . pubertal development
The timing of puberty often matters more than the biology itself. A review of developmental psychology highlights the : On average, the process typically starts between ages