From: Testicular volumes revisited: A proposal for a simple clinical method that can closely match the volumes obtained by ultrasound and its clinical application
Gonadal stage
Number of measurements
Mean ± SD
G-1
36
0.17 ± 0.02
G-2
28
0.15 ± 0.02
G-3
18
0.16 ± 0.01
G-4
31
0.19 ± 0.02
G-5
22
0.20 ± 0.03
Adults
0.21 ± 0.03