What defines adrenarche in girls?

Adrenarche in girls is defined by the early presence of pubic hair, which occurs due to increased androgen production from the adrenal glands. This stage marks a critical point in the onset of puberty and typically precedes other secondary sexual characteristics. The development of pubic hair indicates that the body is transitioning through hormonal changes and preparing for further developments that accompany puberty.

Other developments such as the growth of breast tissue, the onset of menstruation, and growth spurts occur at different stages of puberty and can be influenced by various factors, but they are not specifically defined as adrenarche. Adrenarche is primarily focused on the hormonal changes and physical changes associated with androgen secretion, making the presence of pubic hair the defining feature of this developmental stage in girls.