Diagrammatic representation of Tanner stages I to V of penis maturation in boys
Diagrammatic representation of Tanner stages I to V of penis maturation in boys
Diagrammatic representation of Tanner stages I to V of penis maturation in boys

Adapted from Figure 1 in Marshall WA, Tanner JM: Variations in the pattern of pubertal changes in boys. Arch Dis Child 45(239):13–23, 1970.