Plasma testosterone was investigated by gas-liquid chromatography with an electron capture detector in a cross-sectional study in childhood and during puberty in 214 boys. The testosterone values were correlated with sexual characteristics such as axillary hair, pubic hair, testicular size and bone age.
In 22 individuals during puberty a longitudinal study was started, indicating a very steep increase of plasma testosterone between 40 and 240 ng/100 ml. This stage is mostly passed through very rapidly within 10 months.
Plasma testosterone, growth velocity and weight gain were correlated in two boys during puberty. The peak of growth spurt occurs between 50 and 170 ng of plasma testosterone.