Adrenarche

Adrenarche is an early stage in sexual maturation that happens in some higher primates (including humans), typically peaks at around 20 years of age,[1][2] and is involved in the development of pubic hair, body odor, skin oiliness, axillary hair, sexual attraction/sexual desire/increased libido and mild acne.

[1][4][5] Unlike the physical changes that occur during puberty, adrenarche is primarily an emotional and psychological stage of development.

A third avenue of research is pursuing a possible relationship with either fetal or childhood body mass and related signals such as insulin and leptin.

Adrenarche also occurs prematurely in many children who are overweight, suggesting a possible relationship with body mass or adiposity signals.

In most boys, these changes are indistinguishable from early testicular testosterone effects occurring at the beginning of gonadal puberty.

Parents and many physicians often infer (incorrectly) the onset of puberty from the first appearance of pubic hair (termed pubarche).

[citation needed] However, the independence of adrenarche and gonadal puberty is apparent in children with atypical or abnormal development, when one process may occur without the other.

For instance, adrenarche does not occur in many girls with Addison's disease, who will continue to have minimal pubic hair as puberty progresses.