Adrenarche
Adrenarche is an early stage in
Occurrence
Adrenarche occurs starting at the age of 6 years.
Role in puberty
An initiator of adrenarche has not yet been identified. Researchers have unsuccessfully tried to identify a new pituitary peptide, to be called "adrenal androgen stimulating hormone". Others have proposed that adrenarchal maturation is a gradual process intrinsic to the adrenal glands that has no distinct trigger. 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. Many children born small for gestational age (SGA) because of intrauterine growth restriction (IUGR) have an earlier onset of adrenarche, which raises the possibility that timing of adrenarche may be affected by physiological programming in infancy. Adrenarche also occurs prematurely in many children who are overweight, suggesting a possible relationship with body mass or adiposity signals.
The principal physical consequences of adrenarche are
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. Conversely, girls with Turner syndrome will have normal adrenarche and normal pubic hair development, but true gonadal puberty never occurs because their ovaries are abnormal.
Premature adrenarche
Premature adrenarche is the most common cause of the early appearance of pubic hair ("premature pubarche") in childhood. In a large proportion of children it seems to be a variation of normal development requiring no treatment. However, there are three clinical issues related to premature adrenarche.
First, when pubic hair appears at an unusually early age in a child, premature adrenarche should be distinguished from true central
Second, there is some evidence that premature adrenarche may indicate that there was an abnormality of the intrauterine energy environment and of intrauterine growth. As mentioned above, premature adrenarche occurs more often in children with intrauterine growth retardation and in overweight children. Some of these same studies have demonstrated that some girls who display premature adrenarche may continue to have excessive androgen levels in adolescence. This can result in hirsutism or menstrual irregularities due to anovulation, referred to as polycystic ovary syndrome.
Third, at least one report[7] from 2008 found an increased incidence of behavior and school problems in a group of children with premature adrenarche compared with an otherwise similar control group. To date, such a relationship has neither been confirmed nor explained and there are no obvious management implications.
Other primates
Adrenarche occurs in only a small number of primates, and only chimpanzees and gorillas show a pattern of adrenarche development similar to humans.[8]
See also
References
- ^ ISBN 978-1-4557-5973-6.
- ^ ISBN 978-3-11-081116-2.
- PMID 2029889.
- ^ ISBN 978-0-7817-1750-2.
- ^ ISBN 978-3-642-02202-9.
- ^ "Everything You Need to Know About Adrenarche: A Surge in Hormones That Happens Before Puberty". Parents. Retrieved 2019-12-31.
- PMID 18655525.
- PMID 155005.
External links
- Adrenarche at the U.S. National Library of Medicine Medical Subject Headings (MeSH)