Precocious puberty

From Wikipedia, the free encyclopedia

Jump to: navigation, search
Precocious puberty
Classification and external resources
ICD-10 E30.1, E22.8
ICD-9 259.1
OMIM 176400
DiseasesDB 10519
MedlinePlus 001168
eMedicine ped/1882
MeSH D011629

Precocious puberty (Latin: pubertas praecox) is an unusually early onset of puberty, the process of sexual maturation triggered by the brain or exogenous chemicals, which usually begins in late childhood and results in reproductive maturity and completion of growth. Early puberty may be a variation of normal development, or may be a result of a disease or abnormal hormone exposure.

In some contexts, the term "precocious puberty" is used more broadly to describe the early appearance of any of the physical features of puberty, even if the complete brain-directed process is not occurring.

Contents

[edit] Types

Early pubic hair, breast, or genital development may result from natural early maturation or from several other conditions.

a.   Early puberty which is natural in every way except age is termed idiopathic central precocious puberty. It may be partial or transient. Central puberty can also occur prematurely if the inhibitory system of the brain is damaged, or a hypothalamic hamartoma produces pulsatile gonadotropin-releasing hormone (GnRH).

b.   Secondary sexual development induced by sex steroids from other abnormal sources (gonadal or adrenal tumors, congenital adrenal hyperplasia, etc.) is referred to as peripheral precocious puberty or precocious pseudopuberty.

[edit] Clinical and social significance

Medical evaluation is sometimes necessary to recognize the few children with serious conditions from the majority who have entered puberty early but are still medically normal. Early sexual development deserves evaluation because it may:

  1. induce early bone maturation and reduce eventual adult height
  2. indicate the presence of a tumor or other serious problem
  3. cause the child, particularly a girl, to become an object of adult sexual interest[1][2][3][4][5]

Earlier puberty is believed to put girls at higher risk of sexual abuse, teasing or bullying, mental health disorders and short stature as adults.[1][3][6][4][5] Helping children control their weight is suggested to help delay puberty.[1] Early puberty additionally puts girls at a "far greater" risk for breast cancer later in life.[3] Girls as young as 8 are increasingly starting to menstruate, develop breasts and grow pubic and underarm hair; these "biological milestones" only typically occurred at 13 or older decades ago.[3] African American girls are especially prone to early puberty. There are theories debating the trend of early puberty, but the exact causes are not known. "This is a review of what we know; it's absolutely superb," said Dr. Marion Kavanaugh-Lynch, an oncologist and director of the California Breast Cancer Research Program in Oakland, which directs tobacco tax proceeds to research projects. "The data indicates that if you get your first period before age 12, your risk of breast cancer is 50 percent higher than if you get it at age 16," said the report's author, biologist Sandra Steingraber, herself a cancer survivor. "For every year we could delay a girl's first menstrual period, we could prevent thousands of breast cancers."[3]

Though boys face less problems upon early puberty than girls, early puberty is not always positive for boys; early sexual maturation in boys can be accompanied by increased aggressiveness due to the surge of hormones that affect them.[7] Because they appear older than their peers, pubescent boys may face increased social pressure to conform to adult norms; society may view them as more emotionally advanced, despite the fact that their cognitive and social development may lag behind their appearance.[7] Studies have shown that early maturing boys are more likely to be sexually active and are more likely to participate in risky behaviors.[8]

Central precocious puberty can be caused by intracranial neoplasm, infection, trauma, hydrocephalus, and Angelman syndrome.[9] Bones can be considered older in individuals with early puberty. Early puberty is marked by growth hormone problems resulting from various brain disorders. Precocious puberty can make a child able to conceive when very young; the youngest mother on record is Lina Medina, who gave birth at the age of 5 years, 7 months and 21 days.

High levels of beta-hCG in serum and cerebrospinal fluid observed in a 9-year-old boy suggest a pineal gland tumor. The tumor is called a chorionic gonadotropin secreting pineal tumor. Radiography and chemotherapy reduced tumor and beta-hCG levels normalized.[10] "Central precocious puberty (CPP) was reported in some patients with suprasellar arachnoid cysts(SAC) [3], and SCFE occurs in patients with CPP because of rapid growth and changes of growth hormone secretion."[11]

[edit] Diagnostic criteria

Studies indicate that breast development in girls and pubic hair in girls and boys are starting earlier than in previous generations.[1][12][13][14][15] As a result, "early puberty" in children, particularly girls, as young as 9 and 10 is no longer considered abnormal, although it may be upsetting to parents[1][15] and can be harmful to children who mature physically at a time when they are immature mentally.[16]

No single age limit reliably separates normal from abnormal processes in children today, but the following age thresholds for evaluation will minimize the risk of missing a significant medical problem:

  • Pubic hair or genital enlargement in boys with onset before 9.5 years.
  • Breast development in boys before appearance of pubic hair and testicular enlargement.
  • Pubic hair before 8 or breast development in girls with onset before 7 years.
  • Menstruation in girls before 10 years.

[edit] Causes

The causes of early puberty are somewhat unclear, though girls who have a high-fat diet and are not physically active or are obese are more likely to physically mature earlier.[1][17] Exposure to chemicals that mimic estrogen (known as xenoestrogens) is a possible cause of early puberty in girls.

Bisphenol A (BPA) is a chemical used in hard plastics, and is frequently used to make baby bottles, water bottles, sports equipment, and medical devices. It is also in an epoxy used as a coating in almost all food and beverage cans in most countries. Scientists are concerned about BPA's behavioral effects on fetuses, infants, and children at current exposure levels because it can affect the prostate gland or mammary gland, and lead to early puberty in girls, and possibly cancer later in life. BPA mimics and interferes with the action of estrogen, which is an important reproduction and development regulator. It leaches out of plastic into liquids and foods.[1]

There are also medical causes of early puberty. For example, an 8-year-old boy had early puberty caused by a malignant intracranial germ cell tumor.[18] Antoniazzi F, Zamboni G (2004). "Central precocious puberty: current treatment options". Paediatr Drugs 6 (4): 211–31. PMID 15339200. )

The role of the pineal gland in reproduction of other species of vertebrate suggest that the pineal gland does have significance in development and function of human reproductive axis.[19]

In a study using neonatal melatonin on rats, results suggest that elevated melatonin could be responsible for some cases of early puberty.[20]

[edit] Treatment

One possible treatment is with anastrozole. Histrelin acetate (Supprelin) or Leuprolide, both GnRH agonists, may also be used. GnRH agonists stimulate the pituitary to release Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH). However, when used regularly, GnRH agonists cause a decreased release of FSH and LH. GnRH produced by the hypothalamus is pulsatile, allowing for a physiologic release of FSH and LH.

[edit] See also

[edit] References

  1. ^ a b c d e f g ""RIGHT NOW: Working for You: Today's Jobs Doctors: Chemical Exposure, Obesity Behind Early Puberty For Girls". fox4kc.com. November 9, 2009. http://www.fox4kc.com/lifestyle/health/wdaf-doctors-obesity-puberty-110909,0,6425105.story. Retrieved 2009-11-10. 
  2. ^ "GIRLS AND ALCOHOL". casacolumbia.org. http://www.casacolumbia.org/absolutenm/articlefiles/412-GIRLS%20AND%20ALCOHOL_CASA%20Fact%20Sheet.pdf. Retrieved 2009-12-15. 
  3. ^ a b c d e "Early-Onset Puberty Puts Girls at Risk of Medical Problems". redorbit.com. 2007-09-17. http://www.redorbit.com/news/health/1067387/earlyonset_puberty_puts_girls_at_risk_of_medical_problems/index.html. Retrieved 2009-12-15. 
  4. ^ a b (Stattin & Magnussion, 1990).
  5. ^ a b (Caspi et al.1993: Lanza and Collins, 2002)
  6. ^ (Peterson, 1987)
  7. ^ a b Garn, SM. Physical growth and development. In: Friedman SB, Fisher M, Schonberg SK. , editors. Comprehensive Adolescent Health Care. St Louis: Quality Medical Publishing; 1992. Retrieved on 2009-02-20
  8. ^ Susman, EJ; Dorn, LD; Schiefelbein, VL. Puberty, sexuality, and health. In: Lerner MA, Easterbrooks MA, Mistry J. , editors. Comprehensive Handbook of Psychology. New York: Wiley; 2003. Retrieved on 2009-02-20
  9. ^ Dickerman R, Stevens Q, Steide J, Schneider S (2004). "Precocious puberty associated with a pineal cyst: is it disinhibition of the hypothalamic-pituitary axis?". Neuro Endocrinol Lett 25 (3): 173–5. PMID 15349080. 
  10. ^ Kuo H, Sheen J, Wu K, Wei H, Hsiao C. "Precocious puberty due to human chorionic gonadotropin-secreting pineal tumor". Chang Gung Med J 29 (2): 198–202. PMID 16767969. 
  11. ^ Yamato F, Takaya J, Higashino H, Yamanouchi Y, Suehara H, Kobayashi Y (2005). "Slipped capital femoral epiphysis during the treatment of precocious puberty with a gonadotropin-releasing hormone-agonist: aetiological considerations". Eur. J. Pediatr. 164 (3): 173–4. doi:10.1007/s00431-004-1578-7. PMID 15592875. 
  12. ^ "Onset of Breast and Pubic Hair Development in 1231 Preadolescent Lithuanian Schoolgirls". adc.bmj.com. http://adc.bmj.com/cgi/content/abstract/adc.2004.057612v1. Retrieved 2007-12-06. 
  13. ^ "American Boys Are Reaching Puberty Early". VRP Staff. http://www.vrp.com/articles.aspx?ProdID=art677&zTYPE=2. Retrieved 2009-02-21. 
  14. ^ Simpson, Elizabeth (2001-02-08). "PUBERTY HITTING GIRLS EARLIER, DOCTORS SAY STUDY REVEALS GIRLS DEVELOPING AT 8 OR 9 RATHER THAN 10 OR 11.". The Virginian-Pilot (Norfolk, VA). 
  15. ^ a b Ritter, Jim (2000-08-02). "Parents worried by girls' earlier start of puberty". Chicago Sun-Times. 
  16. ^ Diana Zuckerman Ph.D. (2001). "When Little Girls Become Women: Early Onset of Puberty in Girls". The Ribbon. Cornell University Program on Breast Cancer and Environmental Risk Factors. http://www.center4research.org/children11.html. Retrieved 14 January 2010. 
  17. ^ (Tanner, 1990).
  18. ^ Massie R, Shaw P, Burgess M (1993). "Intracranial choriocarcinoma causing precocious puberty and cured with combined modality therapy". J Paediatr Child Health 29 (6): 464–7. PMID 8286166. 
  19. ^ Cavallo A (1993). "Melatonin and human puberty: current perspectives". J Pineal Res 15 (3): 115–21. doi:10.1111/j.1600-079X.1993.tb00517.x. PMID 8106956. 
  20. ^ Esquifino A, Villanúa M, Agrasal C (1987). "Effect of neonatal melatonin administration on sexual development in the rat". J Steroid Biochem 27 (4-6): 1089–93. doi:10.1016/0022-4731(87)90194-4. PMID 3121932. (4-6):1089-93

[edit] External links

Retrieved from "http://en.wikipedia.org/wiki/Precocious_puberty"