Talk:Puberty Development: Difference between revisions
mNo edit summary |
mNo edit summary |
||
| Line 6: | Line 6: | ||
==Definitions of stages== | ==Definitions of stages== | ||
Adapted from text by Lawrence Neinstein, M.D.<ref>[http://www.chla.org/site/apps/kb/cs/contactdisplay.asp?c=ipINKTOAJsG&b=3832751&sid=dvKTLhOVJjLXK5POJqE&r=1 Lawrence S. Neinstein, M.D.: Adolescent Medicine - Children's Hospital Los Angeles CA | Adapted from text by Lawrence Neinstein, M.D.<ref>[http://www.chla.org/site/apps/kb/cs/contactdisplay.asp?c=ipINKTOAJsG&b=3832751&sid=dvKTLhOVJjLXK5POJqE&r=1 Lawrence S. Neinstein, M.D.: Adolescent Medicine - Children's Hospital Los Angeles CA | ||
===Genitals (male)=== | ===Genitals (male)=== | ||
; Tanner I | ; Tanner I | ||
: prepubertal ( | : prepubertal (testicular volume less than 1.5 ml; small penis of 3 cm or less) (typically age 9 and younger) | ||
; Tanner II | ; Tanner II | ||
: testicular volume between 1.6 and 6 ml; skin on scrotum thins, reddens and enlarges; penis length unchanged (9–11) | : testicular volume between 1.6 and 6 ml; skin on scrotum thins, reddens and enlarges; penis length unchanged (9–11) | ||
| Line 22: | Line 22: | ||
===Breasts (female)=== | ===Breasts (female)=== | ||
; Tanner I | ; Tanner I | ||
: no glandular tissue: | : no glandular tissue: areola follows the skin contours of the chest (prepubertal) (typically age 10 and younger) | ||
; Tanner II | ; Tanner II | ||
: [[Thelarche|breast bud]] forms, with small area of surrounding glandular tissue; areola begins to widen (10–11.5) | : [[Thelarche|breast bud]] forms, with small area of surrounding glandular tissue; areola begins to widen (10–11.5) | ||
| Line 37: | Line 37: | ||
; Tanner I | ; Tanner I | ||
: no pubic hair at all ( | : no pubic hair at all (prepuberta] state) (typically age 10 and younger) | ||
; Tanner II | ; Tanner II | ||
: small amount of long, downy hair with slight pigmentation at the base of the | : small amount of long, downy hair with slight pigmentation at the base of the penis and scrotum (males) or on the [[labia majora]] (females) (10–11.5) | ||
; Tanner III | ; Tanner III | ||
: hair becomes more coarse and curly, and begins to extend laterally (11.5–13) | : hair becomes more coarse and curly, and begins to extend laterally (11.5–13) | ||
Revision as of 15:40, 2 June 2015
| About Discussion Pages |
|---|
Glossary Links
Cite this page: Hill, M.A. (2024, April 19) Embryology Puberty Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Puberty_Development |
Tanner Stages
Definitions of stages
Adapted from text by Lawrence Neinstein, M.D.<ref>[http://www.chla.org/site/apps/kb/cs/contactdisplay.asp?c=ipINKTOAJsG&b=3832751&sid=dvKTLhOVJjLXK5POJqE&r=1 Lawrence S. Neinstein, M.D.: Adolescent Medicine - Children's Hospital Los Angeles CA
Genitals (male)
- Tanner I
- prepubertal (testicular volume less than 1.5 ml; small penis of 3 cm or less) (typically age 9 and younger)
- Tanner II
- testicular volume between 1.6 and 6 ml; skin on scrotum thins, reddens and enlarges; penis length unchanged (9–11)
- Tanner III
- testicular volume between 6 and 12 ml; scrotum enlarges further; penis begins to lengthen to about 6 cm (11–12.5)
- Tanner IV
- testicular volume between 12 and 20 ml; scrotum enlarges further and darkens; penis increases in length to 10 cm and circumference (12.5–14)
- Tanner V
- testicular volume greater than 20 ml; adult scrotum and penis of 15 cm in length (14+)
Breasts (female)
- Tanner I
- no glandular tissue: areola follows the skin contours of the chest (prepubertal) (typically age 10 and younger)
- Tanner II
- breast bud forms, with small area of surrounding glandular tissue; areola begins to widen (10–11.5)
- Tanner III
- breast begins to become more elevated, and extends beyond the borders of the areola, which continues to widen but remains in contour with surrounding breast (11.5–13)
- Tanner IV
- increased breast size and elevation; areola and papilla form a secondary mound projecting from the contour of the surrounding breast (13–15)
- Tanner V
- breast reaches final adult size; areola returns to contour of the surrounding breast, with a projecting central papilla. (15+)
Pubic hair (both male and female)
- Tanner I
- no pubic hair at all (prepuberta] state) (typically age 10 and younger)
- Tanner II
- small amount of long, downy hair with slight pigmentation at the base of the penis and scrotum (males) or on the labia majora (females) (10–11.5)
- Tanner III
- hair becomes more coarse and curly, and begins to extend laterally (11.5–13)
- Tanner IV
- adult–like hair quality, extending across pubis but sparing medial thighs (13–15)
- Tanner V
- hair extends to medial surface of the thighs (15+)
2012
Testicular volumes revisited: A proposal for a simple clinical method that can closely match the volumes obtained by ultrasound and its clinical application
Int J Pediatr Endocrinol. 2012 Jun 8;2012(1):17. doi: 10.1186/1687-9856-2012-17.
Sotos JF1, Tokar NJ.
Abstract
BACKGROUND: The testicular volumes obtained with the clinical methods, calculated using the ellipsoid equation W2 x L x π/6, correlate with those obtained by ultrasound (US) and are useful clinically, but overestimate ultrasound values, mainly because of the inclusion of the scrotal skin and epididymis, have much variability, and may not be accurate or reproducible.The US measurement is somewhat inconvenient, because it requires another procedure and, mainly, is costly.It would be helpful to have a simple, low cost clinical method that approximates or closely matches the results obtained by ultrasound.Formulas, equivalent to the ellipsoid equations, were developed to calculate testicular volumes with corrections of the width (W), length (L), and height (H) of the testis obtained in the scrotum to avoid the inclusion of the scrotal skin and epididymis. SUBJECTS & METHODS: The US observations in our hospital of the width, height, length, height/width, and length/width ratios and volumes of 110 testes from 55 children from 1 month to 17 ½ years of age were reviewed. Based on these observations and those reported by others, formulas to apply to the clinical measurements were developed to approximate the volumes obtained by ultrasound. The validity and accuracy of the formulas were determined. For the clinical application of the formulas, measurements of the width of the testis in the scrotum, with a centimeter ruler, were obtained in 187 study subjects in different stages of puberty and adults, for a total of 374 testicular determinations. RESULTS: The widths obtained in the scrotum were corrected by subtracting the values of the double scrotal skin. The formulas were then applied and the testicular volumes determined. The testicular volumes were then compared to the ultrasound values reported in hundreds of subjects by four different groups and statistically analyzed. The volumes obtained by the formulas (means ± SD) closely matched the volumes obtained by ultrasound. CONCLUSION: A simple clinical method, based on the width of the testis obtained in the scrotum with a centimeter ruler, which can determine testicular volumes closely matching those reported by ultrasound, is proposed.
PMID 22682237
2010
Quantification of cranial base growth during pubertal growth
Malta LA, Ortolani CF, Faltin K. J Orthod. 2009 Dec;36(4):229-35. PMID: 19934240
2004
BJU Int. 2004 May;93(7):1015-7. Correlation of ultrasonographic and orchidometer measurements of testis volume in adults. Schiff JD1, Li PS, Goldstein M. Author information Abstract OBJECTIVE: To determine the correlation between testicular volume measured with an orchidometer or high-resolution scrotal ultrasonography (US) with colour-flow Doppler analysis. PATIENTS AND METHODS: In all, 159 men (mean age 36.6 years) presenting for infertility evaluation underwent both a physical examination by a one experienced examiner and high-resolution US with colour-flow Doppler analysis. An orchidometer was also used to measure testicular volume after stretching the scrotal skin tightly over the testis and after warming with a heating pad. The US was interpreted by a radiologist who had no knowledge of the orchidometer estimates. The volume was calculated as 0.71 x length x width x height. RESULTS: For the right testes the mean orchidometer and US estimates were 18.4 and 18.3 mL, yielding a correlation coefficient of 0.72 (r (2) = 0.52, P < 0.01). On the left the respective values were 17.1 and 16.9 mL, with a correlation coefficient of 0.69 (r (2) = 0.48, P < 0.01). CONCLUSION: Orchidometer estimates of testicular volume correlate closely and very significantly with US estimates in adults. In the hands of an experienced examiner orchidometer measurements provide an accurate, rapid and inexpensive assessment of testicular volume. PMID 15142154
Puberty
Can occur over a broad range of time and differently for each sex: girls (age 7 to 13) boys (age 9 to 15).
The physical characteristics that can be generally measured are: genital stage, pubic hair, axillary hair, menarche, breast, voice change and facial hair.
The physiological process is initiated by the hypothalmus releasing gonadotropin releasing hormone (GnRH) which signals the pituitary to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH) which in turn signals throughout the body sexual development.
Links: Endocrinology - Puberty | Endocrinology - Endocrine changes in puberty | Endocrinology - Gonad | Clinical Methods - The Adolescent Patient | Clinical Methods - Staging Criteria for Secondary Sexual Development | NICHD - Puberty | UCSF - Male Development |
Precocious Puberty
Premature development of the signs of puberty which can occur in both girls (before age 7 or 8) and in boys (before age 9).
Links: Endocrinology - Precocious sexual development | NICHD - Precocious Puberty | Nemours Foundation - Precocious Puberty | MedlinePlus - Obesity May Trigger Earlier Puberty for Girls | Time Magazine - Teens Before Their Time |
Delayed Puberty
Determined in boys by a lack of increase in testicular volume by the age of 14 years. In girls, no breast development by the age of 13.5 years and a lack of menstruation by the age of 16 years. There can also be a "pubertal arrest" where there is no progress in puberty over 2 year period.
Links: Endocrinology - Delayed puberty | Endocrinology - Definitions and causes of delayed puberty | Nemours Foundation - Delayed Puberty
Kisspeptin
While the hypothalamic expression of gonadotropin releasing hormone (GnRH) is a known puberty trigger, it was not known what initiated the GnRH secretion. Recent research suggests that an earlier signal could come from increased neuronal and hypothalamic expression of a peptide family (kisspeptins) and their receptor (G protein-coupled receptor GPR54) in the hypothalamus. A single gene (Kiss1) encodes these 145 amino acid kisspeptins and it was originally identified as a human metastasis suppressor gene (suppresses melanomas and breast carcinomas without affecting tumorigenicity).
Two hypothalamic nuclei, the arcuate nucleus and anteroventral periventricular nucleus (AVPV), are thought to contain the kisspeptin secreting neurons.
The anteroventral periventricular nucleus differs in males and females (sexually dimorphic). The arcuate nucleus (and medial preoptic area, MPOA) is linked into the olfactory system, through the vomeronasal organ, perhaps in relation to the influence of pheromones on sexual behavior and neuroendocrine function (in mice).
| File:Chockiss.jpeg | Why Kisspeptin?
The original discovery of the peptide was made by scientists located in Hershey, PA, USA and named the gene "Kiss1" after the "Hershey chocolate kiss". |
References: Seminara SB. Mechanisms of Disease: the first kiss-a crucial role for kisspeptin-1 and its receptor, G-protein-coupled receptor 54, in puberty and reproduction. Nat Clin Pract Endocrinol Metab. 2006 Jun;2(6):328-34. | Dungan HM, Clifton DK, Steiner RA. Minireview: kisspeptin neurons as central processors in the regulation of gonadotropin-releasing hormone secretion. Endocrinology. 2006 Mar;147(3):1154-8.
Links: OMIM - KISS1 METASTASIS SUPPRESSOR | OMIM - G-protein-coupled receptor 54 |
Gonadotropin Releasing Hormone (GnRH)
Neurons in the hypothalamic arcuate nucleus (and other nuclei) synthesise this hormone along with gonadotrophin associated peptide (GAP), which are both released and transported by hypophyseal portal capillaries to the anterior pituitary and bound by a membrane receptor.
GnRH increases during early puberty, followed by an increased pituitary responsiveness, then increasing sex steroid levels and then increased nocternal Luteinizing hormone (LH) secretion.
Links: Endocrinology - GnRH and the control of gonadotrophin synthesis and secretion | Endocrinology - Synthesis of GnRH and its actions on pituitary gonadotrophs |
Australian
HealthInsite Puberty
Child and Youth Health (SA) - Puberty
American
National Institute of Child Health and Human Development Puberty | Precocious Puberty
American Academy of Family Physicians Puberty: What to Expect When Your Child Goes through Puberty
Nemours Foundation Precocious Puberty | Delayed Puberty |
Reading
Most embryology textbooks (by definition) do not cover postnatal developmenty in any detail. The links below are to useful scientific external online resources.
- PHYSICAL DEVELOPMENT, GROWTH, MATURATION, AND AGEING
- Patterns of Human Growth (PDF document)
- Causes and Mechanisms of Linear Growth Retardation
The links below are to general public external text resources (this listing is for information purposes only and is not intended as an endorsement of a commercial product).
- Ready, Set, Grow!: A What's Happening to My Body? Book for Younger Girls, by Lynda Madaras and Linda Davick
- What's Happening to My Body? Book for Boys: The New Growing-Up Guide for Parents and Sons, Third Edition by Lynda Madaras, Area Madaras, Dane Saavedra, and Simon Sullivan
- Sex, Puberty, and All That Stuff: A Guide to Growing Up, by Jacqui Bailey and Jan McCafferty
