Pubarche
Encyclopedia
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 androgen
s from the adrenal gland
s 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 gonad
s. 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. However girls tend to begin pubarche earlier than men, as with most puberty
stages and puberty as a whole. The exact age for females varies between 11-13 on average, and for males, about 12.5-14. However, evidence is this age is decreasing
.
Pubic hair
Pubic hair is hair in the frontal genital area, the crotch, and sometimes at the top of the inside of the legs; these areas form the pubic region....
in a child. Pubarche is one of the physical changes of puberty
Puberty
Puberty is the process of physical changes by which a child's body matures into an adult body capable of reproduction, as initiated by hormonal signals from the brain to the gonads; the ovaries in a girl, the testes in a boy...
but should not be equated with it since it may occur independently of complete puberty. Pubarche usually results from rising levels of androgen
Androgen
Androgen, also called androgenic hormone or testoid, is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of male characteristics in vertebrates by binding to androgen receptors...
s from the adrenal gland
Adrenal gland
In mammals, the adrenal glands are endocrine glands that sit atop the kidneys; in humans, the right suprarenal gland is triangular shaped, while the left suprarenal gland is semilunar shaped...
s or the testes but may also result from exposure of a child to an anabolic steroid
Anabolic steroid
Anabolic steroids, technically known as anabolic-androgen steroids or colloquially simply as "steroids", are drugs that mimic the effects of testosterone and dihydrotestosterone in the body. They increase protein synthesis within cells, which results in the buildup of cellular tissue ,...
.
When pubarche occurs prematurely (in early or mid-childhood), it is referred to as premature pubarche and may warrant an evaluation. Premature adrenarche
Adrenarche
Adrenarche is an early sexual maturation stage in some higher primates that in humans typically occurs at around 6 to 8 years of age. During adrenarche the adrenal cortex secretes increased levels of androgens such as DHEA and DHEAS, but without increased cortisol levels. Adrenarche is the result...
is the most common cause of premature pubarche. Rarer causes include precocious puberty
Precocious puberty
As a medical term, precocious puberty describes puberty occurring at an unusually early age. In most of these children, the process is normal in every respect except the unusually early age, and simply represents a variation of normal development. In a minority of children, the early development is...
, congenital adrenal hyperplasia
Congenital adrenal hyperplasia
Congenital adrenal hyperplasia refers to any of several autosomal recessive diseases resulting from mutations of genes for enzymes mediating the biochemical steps of production of cortisol from cholesterol by the adrenal glands ....
, and androgen
Androgen
Androgen, also called androgenic hormone or testoid, is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of male characteristics in vertebrates by binding to androgen receptors...
-producing tumors of the adrenals or gonad
Gonad
The gonad is the organ that makes gametes. The gonads in males are the testes and the gonads in females are the ovaries. The product, gametes, are haploid germ cells. For example, spermatozoon and egg cells are gametes...
s. 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.
Average Age of Pubarche Initiation for Males and Females
See Also: Tanner ScaleThe average beginning of pubarche varies due to many factors, including climate, nourishment, weight, nurture, and genes. However girls tend to begin pubarche earlier than men, as with most puberty
Puberty
Puberty is the process of physical changes by which a child's body matures into an adult body capable of reproduction, as initiated by hormonal signals from the brain to the gonads; the ovaries in a girl, the testes in a boy...
stages and puberty as a whole. The exact age for females varies between 11-13 on average, and for males, about 12.5-14. However, evidence is this age is decreasing
Precocious puberty
As a medical term, precocious puberty describes puberty occurring at an unusually early age. In most of these children, the process is normal in every respect except the unusually early age, and simply represents a variation of normal development. In a minority of children, the early development is...
.
See also
- AdrenarcheAdrenarcheAdrenarche is an early sexual maturation stage in some higher primates that in humans typically occurs at around 6 to 8 years of age. During adrenarche the adrenal cortex secretes increased levels of androgens such as DHEA and DHEAS, but without increased cortisol levels. Adrenarche is the result...
- AndrogenAndrogenAndrogen, also called androgenic hormone or testoid, is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of male characteristics in vertebrates by binding to androgen receptors...
s - MenarcheMenarcheMenarche is the first menstrual cycle, or first menstrual bleeding, in female human beings. From both social and medical perspectives it is often considered the central event of female puberty, as it signals the possibility of fertility....
- PubertyPubertyPuberty is the process of physical changes by which a child's body matures into an adult body capable of reproduction, as initiated by hormonal signals from the brain to the gonads; the ovaries in a girl, the testes in a boy...
- SpermarcheSpermarcheThe first ejaculatory experience of boys is termed semenarche.Spermarche refers to the beginning of development of sperm in boys' testicles at puberty. It contrasts with menarche in girls. Depending on their upbringing, cultural differences, and prior sexual knowledge, boys may have different...
- ThelarcheThelarcheThelarche is the onset of secondary breast development, usually occurring at the beginning of puberty in girls. Its etymology is from Greek θηλή [tʰelḗ], “nipple” and ἀρχή [arkʰḗ], “beginning, onset”. Thelarche is usually noticed as a firm, tender lump directly under the centre of the nipple...