Pubarche

Pubarche refers to the first appearance of pubic hair in a child. Pubarche is one of the physical changes of puberty but should not be equated with it since it may occur independently of complete puberty. Pubarche usually results from rising levels of androgens from the adrenal glands or the testes but may also result from exposure of a child to an anabolic steroid.

When pubarche occurs prematurely (in early or mid-childhood), it is referred to as premature pubarche and may warrant an evaluation. Premature adrenarche is the most common cause of premature pubarche. Rarer causes include precocious puberty, congenital adrenal hyperplasia, and androgen-producing tumors of the adrenals or gonads. When adrenarche, central puberty, and all pathologic conditions have been excluded, the term isolated premature pubarche is used to describe the unexplained development of pubic hair at an early age without other hormonal or physical changes of puberty.

The average beginning of pubarche varies due to many factors, including climate, nourishment, weight, nurture, and genes. First (and often transient) pubic hair resulting from adrenarche may appear between ages 6-10 well preceding puberty.

During puberty pubarche tends to occur earlier in girls than boys, as with most puberty stages and puberty as a whole. The average age for females varies between 9-12, and for males, about 10-12.

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