The process of maturing sexually and thus when sexual reproduction becomes possible. During puberty, major differences in composition, shape and size, as well as function, are attained in many body parts and systems, the most striking of which are secondary sexual characteristics. These changes are due to increasing levels of estradiol and testosterone taking place in the endocrine reproductive systems of females and males, respectively, and which is referred to as ‘hormonal puberty’. These systems are functional in humans by the end of the first trimester of pregnancy, which are then inhibited at birth, with hormonal activity in the gonads starting again some months later. The mechanisms of inhibition and re-activation are not yet fully understood.
See Adolescent growth spurt, Adolescent voice change, Axillary hair, De Morsier-Kallmann syndrome, Estradiol, Gonadotropin releasing hormone (GnRH), Menarche, Secondary sexual characteristics, Testosterone