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Foreskin

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Foreskin in adulthood: Add text.
<div class='res-img'>[[File:Infographic Foreskin.jpg|Foreskin - Anatomy and function]]</div>
The '''foreskin''' or '''prepuce''' is the double-layered fold of smooth muscle tissue, blood vessels, neurons, [[skin]], and [[mucosa| mucous membrane]] part of the [[penis]] that covers creates the [[preputial sac]], while covering and protects protecting the [[glans penis]] and the [[urinary meatus]].
The nature of the prepuce or foreskin, which is amputated and destroyed by circumcision, must be considered and fully understood in any discussion of male [[circumcision]].<ref name="cold-taylor1999">{{ColdCJ TaylorJR 1999}}</ref>
Purpura et al. (2018) describe described the foreskin as follows:
<blockquote>
Few parts of the human anatomy can compare to the incredibly multifaceted nature of the human foreskin. At times dismissed as “just [[skin]],” the adult foreskin is, in fact, a highly vascularized and densely innervated bilayer tissue, with a surface area of up to 90 cm, and potentially larger. On average, the foreskin accounts for 51% of the total length of the penile [[shaft skin]] and serves a multitude of functions. The tissue is highly dynamic and biomechanically functions like a roller bearing; during intercourse, the foreskin “unfolds” and glides as abrasive friction is reduced and lubricating fluids are retained. The sensitive foreskin is considered to be the primary erogenous zone of the male [[penis]] and is divided into four subsections: [[Preputial mucosa|inner mucosa]], [[ridged band]], [[frenulum]], and outer foreskin; each section contributes to a vast spectrum of sensory pleasure through the [[gliding action]] of the foreskin, which mechanically stretches and stimulates the densely packed corpuscular receptors. Specialized immunological properties should be noted by the presence of [[Langerhans cells]] and other lytic materials, which defend against common microbes, and there is robust evidence supporting [[HIV]] protection. The [[glans penis| glans]] and inner [[mucosa]] are physically protected against external irritation and contaminants while maintaining a healthy, moist surface. The foreskin is also immensely vascularized and acts as a conduit for essential blood vessels within the penis, such as supplying the [[glans]] via the frenular artery.<ref>{{REFjournal
===Foreskin in infancy and childhood===
 Baby boys are born with the foreskin fused with the [[glans penis]] by the balanopreputial lamina, a [[synechia| synechial membrane]], which prevents retraction. In addition, the tip of the foreskin ([[acroposthion]]) is usually too narrow to allow [[retraction of the foreskin]]. The [[preputial cavity sac]] is closed by the synechia and cannot be infected.<ref name="fleiss-hodges-vanhowe1998"/>
Forcible attempts to retract the foreskin result in injury to the boy, so should be avoided. The first person to retract the foreskin should be the boy himself.<ref name="Wright1994">{{REFjournal
|accessdate=2019-11-14
}}</ref>
 
===Foreskin in adolescence===
The foreskin is in a transitional state during puberty and adolesence in which it is changing from the non-retractile foreskin of childhood to thh fully retractable foreskin of adulthood. Many adolescents complain of a non-retractable foreskin. Many need to do manual [[stretching]]. They usually achieve full retraction by age 16.
===Foreskin in adulthood===
The foreskin (also known as the ''prepuce'') is the double-layered fold of smooth muscle tissue, blood vessels, neurons, [[skin]], and [[Preputial mucosa|mucous membrane]] part of the [[penis ]] that covers and protects the [[glans penis]] and the urinary meatus.<ref name="cold-taylor1999"/> There are four layers in the foreskin. The top layer is either epidermis in the outer foreskin or [[mucosa]], in the inner foreskin. The second layer is the lamina propria. The third layer is the [[dartos]]. The fourth layer is the dermis. It is normal for the foreskin to be darker in color than the rest of one's body after puberty. This condition is called hyperpigmentation.  The adult foreskin measures about 3 inches by 5 inches or [[The Foreskin: 15 Square Inches of Erogenous Tissue| 15 square inches]].<ref name="taylor1996">{{TaylorJR LockwoodAP TaylorAJ 1996}}</ref> The foreskin creates the [[preputial sac]]. The two foreskin layers provide a [[skin]] reserve. When the penis becomes erect, the foreskin may wholly or partially unfold to provide the necessary [[skin]] to allow for expansion of the penis during [[erection]].
The foreskin is the movable part of the [[penis]]. The foreskin is not attached to the underlying structure and is free to [[gliding action| glide back and forth]].<ref name="lakshmanan-prakash1980">{{REFjournal
|last=Lakshmanan
|init=S
|url=http://www.cirp.org/library/anatomy/lakshmanan/
|quote=
|pubmedID=
|pubmedCID=
|DOI=
|accessdate=
}}</ref> The [[gliding action]] reduces the friction of intercourse and helps to prevent abrasions, while conserving vaginal lubrication and moisture.<ref name="warren-bigelow1994">{{REFjournal
|journal=Brit J Sex Med
|date=1994-09
|volume=
|issue=
|pages=
|url=http://www.cirp.org/library/general/warren2/
|quote=
}}</ref> The foreskin is attached to the [[glans penis]] on the ventral side by the [[frenulum]], which usually limits [[Retraction of the foreskin| retraction]] to a widely variable degree. The [[ridged band]] emanates from the frenulum.<ref name="cold-taylor1999" />
The epithelium of the outer layer of the foreskin is true [[skin]] while the epithelium of the inner layer is [[Preputial mucosa|mucosal membrane]]. There is a mucocutaneous boundary at the tip of the foreskin. The mucocutaneous junction is a specific erogenous zone.,<ref name="winklemann1959">{{WinkelmannRK 1959}}</ref> Taylor et al. reported:
<blockquote>
The vascular ridges of the `ridged band' and its [[Meissner's corpuscles]] firmly separate preputial epithelium from true [[skin]] and place preputial [[mucosa]] amongst other mucocutaneous [[mucosa]]e. Winkelmann emphasized the structural and functional importance of junctional regions of the body and focused on mucocutaneous end-organs, or `genital corpuscles', of the [[glans penis ]] and prepuce. Some of these end-organs resemble Krause end-bulbs; others resemble [[Meissner's corpuscles]]. … [[Meissner's corpuscles]] of the prepuce may be compared with similar nerve-endings in the finger-tips and lips, which respond in a fraction of a second to contact with light objects that bring about deformation of their capsules. … The prepuce provides a large and important platform for several nerves and nerve endings. The innervation of the outer [[skin]] of the prepuce is impressive; its sensitivity to light touch and pain are similar to that of the [[skin]] of the penis as a whole.<ref name="taylor1996" />
</blockquote>
}}</ref> The adult foreskin frequently has prominent visible veins.
The layer of [[dartos]] muscle is contained within the foreskin.<ref name="cold-taylor1999 /> It makes the foreskin rather stretchy. The dartos muscle keeps the foreskin snugly against the [[glans]]. The fibers of the [[dartos ]] muscle form a whorl at the tip that functions as a sphincter. The sphincter opens to allow [[urine]] to flow out, but closes to protect the [[penis ]] from foreign matter, contaminants, and pathogens.<ref name="lakshmanan-prakash1980"/><ref>{{REFjournal
|last=Jefferson
|first=
|accessdate=2019-10-14
}}</ref>
 
===Foreskin length===
Natural foreskins are found in all lengths from very short to very long. Most fall near the center of the range.
|accessdate=2022-06-21
}}</ref>
 
<i>See [[Development_of_retractable_foreskin#Adult_foreskin| Adult foreskin]].</i>
==Physiological functions==
|ISBN=978-0-553-20429-2
|accessdate=2022-06-16
}}</ref> misled medical science into believing that the foreskin had no function. This meant the foreskin could be excised without doing harm. In actuality, the foreskin has many functions, so its [[amputation]] does [[Bodily harm| great harm]].<ref name="hill2017">{{REFjournal |last=Hill |first=George |init=G |author-link=George Hill |title=The case against circumcision |journal=Journal of Men's Health and Gender |date=2007 |volume=4 |issue=3 |pages=318-323 |url=https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=04ace5046cc27f01b8fbe4aa359c059778983912 |quote= |format=PDF |accessdate=2023-10-01}}</ref>
=== Protective functions ===
}}</ref>
In the absence of the foreskin about ten to twenty percent of [[circumcised]] boys suffer urethral stricture ([[meatal stenosis]]) requiring further treatment.<ref name="frisch2016">{{REFjournal
|last=Frisch
|first=Morten
|DOI=10.1016/j.surge.2016.11.002
|accessdate=2019-10-23
}}</ref> Frisch & Simonsen (2016) reported the incidence of meatal stenosis to be 3.7 times higher in [[circumcised ]] boys.<ref name="frisch2016"/>
The foreskin continues to protect the [[glans penis ]] throughout life, keeping it smooth, glossy, moist, [[Foreskin sensitivity| sensitive]], and free from [[keratinization]] and loss of sensation.
=== Immunological functions ===
Fleiss et al. (1998) have listed numerous immunological functions of the foreskin that help to protect the human body against [[infection]]. The foreskin maintains the moistness of the [[preputial mucosa]] and the [[glans penis]] by [[transudation]]. The sub-preputial moisture contains cathepsin B, chymotrypsin, neutrophil elastase, cytokines, and lysozyme, which has the capacity to desttroy destroy the cell walls of bacteria. The preputial muscles keep the tip of the foreskin closed to keep out pathogens.<ref name="fleiss-hodges-vanhowe1998"/>
The foreskin is highly vascularized. The high rate of blood flow helps to prevent infection.<ref name="fleiss-hodges-vanhowe1998"/>
=== Sexual functions ===
The foreskin is a sexual organ. <ref name="hill2017" /> It provides both mechanical and erogenous functions in sexual intercourse, as well as [[pheromone| pheromones]].<ref name="fleiss-hodges-vanhowe1998"/> Winkelmann (1959) classified the foreskin as ''specific erogenous tissue''.<ref name="winklemann1959" /> When the [[penis ]] becomes erect, the foreskin unfolds to provide the skin necessary to allow the [[penis ]] to expand to full size and length.
The [[gliding action]] provides stimulation and facilitates intromission.<ref name="warren-bigelow1994"/><ref name="morgan1965">{{REFjournal
|DOI=10.1016/s0306-9877(02)00250-5
|accessdate=2019-10-15
}}</ref> At times of sexual arousal, the foreskin may be lubricated by [[pre-ejaculate]]. During the thrusting of sexual congress, the [[gliding action]] reduces abrasions and irritation in the [[Vagina| female partner]] and avoids problems with vaginal dryness.<ref name="warren-bigelow1994"/><ref name="morgan1965"/> The foreskin may protect the corona glandis from hyperstimulation hyper-stimulation and prevent [[premature ejaculation]].
===Sensory functions===
Nature designed the foreskin to be an [[Foreskin sensitivity| erogenous sensory organ]]. <ref name="hill2017" /> The foreskin has a layer of muscle called the [[dartos]] muscle sheath that provides the foreskin with elasticity, flexibility, and stretchiness, which allows full stimulation of the nerves in the [[ridged band]] that sense movement and [[stretching ]] to provide [[foreskin sensitivity]]. There is a mucocutaneous region at the tip of the foreskin where outer skin changes to inner [[mucosa]]. Winkelmann (1959) identified the foreskin as a ''specific erogenous zone'' (meaning an area of acute erogenous sensation). Winklemann reported rete ridges in the foreskin with nerves set close to the surface with closely set networks.<ref name="winklemann1959"/>
Lakshamanan & Prakash (1980) report the "prepuce covers the [[glans ]] completely and snugly like a hosiered material and continues to do so through the entire span of life of the male", which they explain as being caused by the smooth muscle fibers within the prepuce. The prepuce is free to [[gliding action| glide back and forth]]. When it does, it must stretch to go over the glans penis.<ref name="lakshmanan-prakash1980" />
Taylor et al. (1996) carried out a histological study of the foreskin. (Histology is the microscopic examination of cells and tissues.) Taylor et al. found an area of rete ridges just inside the tip of the foreskin that he called the [[ridged band]]. The ridges were found to have nerve endings at the top of the ridges. They report that the ridged band area moves to the shaft of the penis when the penis becomes erect where the nerves are subject to stimulation. They stated:
</blockquote>
Bronselaer et al. (2013) surveyed a large group of [[intact ]] and [[circumcised ]] men in Belgium. They reported:
<blockquote>
Of the men in Group A [intact males], 90.6% rated the sexual pleasure provided when the foreskin was stimulated by themselves or their partners from ‘mild’ to ‘very strong’ and 61.9% the respective orgasm from ‘mild’ to ‘very strong’.
}}</ref>
===Sexual behavior===
Laumann et al. (1997) reported that men who lack a foreskin "engage in a somewhat more elaborated set of sexual practices than do men who are not [[circumcised]]. For each of the practices examined, lifetime experience of various forms of oral and anal sex and [[masturbation]] frequency in the past year, [[circumcised ]] men engaged in these behaviors at greater rates. The difference between [[circumcised ]] men was greatest for [[masturbation]] — ironically, a practice that [[circumcision]] was once thought to limit. A total of 47% of circumcised men reported masturbating at least once a month vs 34% for their [[uncircumcised]] peers."<ref name="laumann1997>{{REFjournal
|last=Laumann
|init=EO
Cold & Taylor (1999) commented, "The increased frequency of [[masturbation]], anal intercourse and fellatio reported by [[circumcised]] men in the [[United States of America| USA]] may possibly be due to the sensory imbalance caused by [[circumcision]]. Clearly, [[amputation]] of the prepuce causes changes in sexual behaviour in human males and females."<ref name="cold-taylor1999" />
Frisch et al. (2011) surveyed the sexual function and behavior of a large group of [[intact]] and [[circumcised]] men in [[Denmark]]. They reported that "[[circumcised ]] men were more likely (38%) than [[uncircumcised]] men (28%) to report ≥10 sex partners."<ref name="frisch lindholm groenbaek 2011">{{FrischM LindholmM GroenbaekM 2011}}</ref>
==The role of the foreskin in heterosexual relations==
}}</ref>
</blockquote>
As previously reported, the foreskin reduces the force required for penetration of the female partner's [[vagina]] by as much as ninety percent.<ref name="taves2002"/> The [[gliding action ]] of the foreskin reduces friction and abrasion, while conserving vaginal lubrication.<ref name="warren-bigelow1994"/>
In a first of its kind, O'Hara & O'Hara (1999) carried out a retrospective survey of 138 women with experience of both [[intact]] and [[circumcised]] partners. The women overwhelmingly concurred that the mechanics of [[sexual intercouse| coitus]] was different for the two groups of men. Of the women, 73% reported that [[circumcised ]] men tend to thrust harder and deeper, using elongated strokes, while unaltered men by comparison tended to thrust more gently, to have shorter thrusts, and tended to be in contact with the mons pubis and [[clitoris]] more, according to 71% of the respondents. Women with [[intact]] partners had a higher rate of orgasms than women with [[circumcised]] partners. O'Hara & O'Hara concluded:
<blockquote>Clearly, the anatomically complete penis offers a more rewarding experience for the female partner during coitus. While this study has some obvious methodological flaws, all the differences cannot be attributed to them. It is important that these findings be confirmed by a prospective study of a randomly selected population of women with experience with both types of men. It would be useful to examine the role of the foreskin in other sexual activities. Because these findings are of interest, the negative effect of circumcision on the sexual enjoyment of the female partner needs to be part of any discussions providing '[[informed consent]]' before circumcision.<ref name="ohara1998">{{REFjournal
|last=O'Hara
"Circumcision was associated with frequent orgasm difficulties in Danish men and with a range of frequent sexual difficulties in women, notably orgasm difficulties, dyspareunia and a sense of incomplete sexual needs fulfilment."<ref name="frisch lindholm groenbaek 2011"/>
</blockquote>
 
 
<!--
''The following content is part of the [[Circumpendium]].''
The two foreskin layers provide a skin reserve, into which the growing shaft expands during an [[erection]]. Depending to the individual length of a man's foreskin, it thereby retracts more or less far. In some men, the [[foreskin]] still fully covers the glans during an [[erection]], in others the [[glans]] is partly or completely exposed.
In addition, the foreskin, in combination with the [[shaft skin]], allows a natural [[gliding action]]. During intercourse as well as [[masturbation]] the outer skin is in contact with the [[vagina]] or the hand respectively. The penile shaft moves mostly within its skin and the skin only moves at the end of its thrust. Due to this, the friction with the [[vagina]] or hand is reduced. The sexual stimulation mostly occurs through the [[stretching ]] and movement of the [[foreskin], when it is pulled over the glans and back, as well as the direct stimulation of the inner foreskin when it is exposed and comes into direct contact with the vagina or the hand. The [[frenulum]] may limit retraction.
The foreskin in childhood is fused with the glans penis by a [[synechia]].-->
 
==Videos==
<b>Why you need to pull back your foreskin.</b><youtube>v=PcxwW4KH3Wg</youtube><br>Pathologist [[Ken McGrath]], Senior Lecturer in Pathology at the Faculty of Health, [https://www.aut.ac.nz/ Auckland University of Technology] and Member of the New Zealand Institute of Medical Laboratory Scientists, discusses the neurological structures in the foreskin.:<br><br>
<youtube>v=lmToXLVrZ7c</youtube>
Dr. Willam Collins explains the nature of the prepuce.
 
<youtube>v=tggap0Hy1l0</youtube>
<br>
<youtube>v=OfeK75HWW7k</youtube>
{{SEEALSO}}
 
* [[Acroposthion]]
* [[Foreskin Care for Boysof intact, foreskinned boys]]
* [[Foreskin in Motion]]
* [[Foreskin sensitivity]]
* [[Frenulum]]
* [[Gliding action]]
* [[Immunological and protective function of the foreskin]]
* [[Pre-ejaculate]]
* [[Preputial sac]]
* [[Retraction of the foreskin]]
|format=
|quote=
}}
* {{REFbook
|last=Scott
|first=Steve
|init=S
|author-link=Steve Scott
|year=1999
|title=The anatomy and physiology of the human prepuce
|url=https://www.coloradonocirc.org/files/handouts/Anatomy_and_Physiology.pdf
|work=Male and Female Circumcision
|editor=[[George C. Denniston|Denniston]] et al.
|edition=
|volume=
|chapter=
|scope=
|page=
|pages=9-18
|location=New York
|publisher=Kluwer Academic / Plenum Publishers
|ISBN=
|quote=
|accessdate=2022-08-03
|note=
}}
* {{REFweb
|url=https://www.i2researchhub.org/articles/ch-2-the-prepuce-doc-genital-integrity-statement/
|title=Ch. 2: The Prepuce (DOC Genital Integrity Statement)
|last=Hill
|website=[[NOHARMM]]
|accessdate=2020-06-30
}}
* {{REFweb
|url=https://foreskinfunction.org/
|title=Functions of the foreskin
|last=
|first=
|accessdate=2021-05-30
}}
* {{REFweb
|url=http://research.cirp.org/index-e.html
|title=Ridged band: Specialized tissue of the penis
|last=Taylor
|first=John R.
|author-link=John R. Taylor
|publisher=CIRP
|website=
|date=1996
|accessdate=2021-07-21
|format=
|quote=
}}
* {{REFweb
|date=2022-11-06
|accessdate=2022-11-16
}}
* {{REFweb
|url=https://www.youtube.com/watch?v=09gW4TclGqY
|title=The Amazing Foreskin: Learn Integral Anatomy with Gil Hedley
|last=Headley
|first=Gil
|init=
|publisher=
|date=2022
|accessdate=2022-12-03
}}
{{REF}}
[[Category:Parental information]]
[[Category:Penile anatomy]]
[[Category:Male sexuality]]
[[Category:Education]]
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