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Foreskin

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Physiological functions: Wikify.
<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===
}}</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=
|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 ===
=== 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" />
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
==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:
<youtube>v=tggap0Hy1l0</youtube>
<br><youtube>v=OfeK75HWW7k</youtube>
{{SEEALSO}}
* [[Acroposthion]]
|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
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