Name = Foreskin
Latin = prepucium, præputium
GraySubject = 262
GrayPage = 1250
Caption = A penis with the foreskin covering the glans.
Width = 150
Genital tubercle, Urogenital folds
Dorsal artery of the penis
Superficial dorsal vein of the penis
Dorsal nerve of the penis
MeshName = Foreskin
MeshNumber = A05.360.444.492.362
male human anatomy, the foreskin or prepuce (a technically broader term that also includes the clitoral hood, the homologous structure in women) is a retractable double-layered fold of skin and mucous membrane that covers the glans penisand protects the urinary meatus(pronounced IPA|) when the penis is not erect. Contrary to popular belief, it does not always automatically retract during an erection.
The outside of the foreskin is like the skin on the shaft of the penis but the inner foreskin is a
mucous membranelike the inside of the eyelid or the mouth. Like the eyelid, the foreskin is free to move after it separates from the glans, usually by puberty. Smooth muscle fibres keep it close to the glans but make it highly elastic.cite journal |url=http://www.cirp.org/library/anatomy/lakshmanan/ |title=Human prepuce - structure & function |first=S |last=Lakshmanan |coauthors=Prakash, S |journal=Indian J Surg |year=1980 |volume=44 |pages=134–7] The foreskin is attached to the glans with a frenulum which helps retract the foreskin over the glans. At the end of foreskin there is a band of tissue called the ridged bandwhich, according to one study, is rich in nerve endings called Meissner's corpuscles.cite journal |url=http://www.cirp.org/library/anatomy/cold-taylor/ |title=The prepuce |last=Cold |first=CJ |coauthors=Taylor, JR |journal=BJU Int |volume=83 Supp 1 |pages=34–44] According to a study by Sorrells "et al.", the five most sensitive areas of the penis are on the foreskin. [cite journal |url=http://www.doctorsopposingcircumcision.org/pdf/sorrells_2007.pdf |title=Fine-touch pressure thresholds in the adult penis |first=Morris |last=Sorrels |coauthors=James L. Snyder, Mark D. Reiss, Christopher Eden, Marilyn F. Milos, Norma Wilcox and Robert S. Van Howe. |journal=Bjuinternational |year=2007 |volume=99 |pages=864–869]
In children, the foreskin covers the glans completely but in adults this need not be so. Schöberlein [ [http://www.male-initiation.net/library/medicus/schoeberlein.html#start Schöberlein circumcision taboos. Phimosis frenulum and foreskin conditions, phimosis and male initiation] ] found that about 50% of young men had full coverage of the glans, 42% had partial coverage, and in the remaining 8%, the glans was uncovered. After adjusting for
circumcision, he stated that in 4% of the young men the foreskin had spontaneously atrophied (shrunk).
Eight weeks after fertilization, the foreskin begins to grow over the head of the penis, covering it completely by 16 weeks. At this stage the foreskin and glans share an
epithelium(mucous layer) that fuses the two together. It remains this way until the foreskin separates from the glans.cite journal |url=http://www.cirp.org/library/general/gairdner/ |title=The Fate of The Foreskin: a study of circumcision |first=D |last=Gairdner |journal=BMJ |year=1949 |volume=2 |pages=1433–7]
At birth, the foreskin is usually still fused with the glans. As childhood progresses the foreskin and the glans gradually separate, a process that may not be complete until late puberty. [cite journal |url=http://www.cirp.org/library/general/oster/ |title=Further fate of the foreskin: incidence of preputial adhesions, phimosis, and smegma among Danish schoolboys |first=J |last=Øster |journal=Arch Dis Child |year=1968 |volume=43 |pages=200–3] Thorvaldsen and Meyhoff reported that average age of first foreskin retraction in Denmark is 10.4 years. [ [http://www.cirp.org/library/normal/thorvaldsen1/ Phimosis: Pathological or Physiological?] ] Wright argues that forcible retraction of the foreskin should be avoided and that the child himself should be the first one to retract his own foreskin. [cite journal |author=Wright JE |title=Further to "the further fate of the foreskin". Update on the natural history of the foreskin |journal=Med. J. Aust. |volume=160 |issue=3 |pages=134–5 |year=1994 |month=February |pmid=8295581 |doi= |url=http://www.cirp.org/library/normal/wright2/] Premature retraction may be painful, and may result in infection.
World Health Organizationstate that there is "debate about the role of the foreskin, with possible functions including keeping the glans moist,protecting the developing penis in utero, or to enhance sexual pleasure due to the presence of nerve receptors". [cite web |title=Male circumcision: Global trends and determinants of prevalence, safety and acceptability |publisher=World Health Organization |url=http://www.who.int/entity/hiv/topics/malecircumcision/JC1320_MaleCircumcision_Final_UNAIDS.pdf |pages=18]
Taylor "et al" described the foreskin in detail, documenting a ridged band of mucosal tissue. They stated "This ridged band contains more Meissner's corpuscles than does the smooth mucosa and exhibits features of specialized sensory mucosa." [cite journal |url=http://www.blackwell-synergy.com/doi/pdf/10.1046/j.1464-410X.1996.85023.x |last=Taylor |first=JR |coauthors=Lockwood, AP; Taylor, AJ |title=The prepuce: specialized mucosa of the penis and its loss to circumcision |journal=Br J Urol |year=1996 |volume=77 |pages=291–5 |doi=10.1046/j.1464-410X.1996.85023.x ] In 1999, Cold and Taylor stated "The prepuce is primary, erogenous tissue necessary for normal sexual function." Boyle "et al", state that "The complex innervation of the foreskin and frenulum has been well-documented, and the genitally intact male has thousands of fine touch receptors and other highly erogenous nerve endings—many of which are lost to circumcision, with an inevitable reduction in sexual sensation experienced by circumcised males." [cite journal |title=Male Circumcision: Pain, Trauma and Psychosexual Sequelae |author=Boyle, G; Goldman, R; Svoboda, J; Fernandez E |journal=Journal of Health Psychology |volume=7 |pages=329–343 |url=http://www.cirp.org/library/psych/boyle6/ |doi=10.1177/1359105302007003225 |year=2002] The AAP noted that the work of Taylor "et al" "suggests that there may be a concentration of specialized sensory cells in specific ridged areas of the foreskin." [cite journal |title=American Academy of Pediatrics: Circumcision Policy Statement |journal=Pediatrics |month=March |year=1999 |volume=103 |pages=686–693 |url=http://aappolicy.aappublications.org/cgi/content/full/pediatrics%3b103/3/686 |pmid=10049981 |doi=10.1542/peds.103.3.686]
Moses and Bailey (1998), describe the evidence of sensory function as "indirect," and state that "aside from anecdotal reports, it has not been demonstrated that this is associated with increased male sexual pleasure." [cite journal |author = Moses S |coauthors = Bailey RC, Ronald AR |title = Male circumcision: assessment of health benefits and risks |journal = Sexually Transmitted Infections |volume = Vol 74 |issue = Issue 5 |pages = 368–373 |date = 1998 |url = http://sti.bmj.com/cgi/reprint/74/5/368 |accessdate = 2007-04-28 |quote = There is indirect evidence suggesting that the foreskin may have an important sensory function, although aside from anecdotal reports, it has not been demonstrated that this is associated with increased male sexual pleasure.] The World Health Organisation states that there is little evidence for diminished sexual function, adding that studies have been inconsistent. [cite web |title=Male circumcision: Global trends and determinants of prevalence, safety and acceptability |publisher=World Health Organization |url=http://www.who.int/entity/hiv/topics/malecircumcision/JC1320_MaleCircumcision_Final_UNAIDS.pdf |pages=22 |quote=Although it has been argued that sexual function may diminish following circumcision due to the removal of the nerve endings in the foreskin and subsequent thickening of the epithelia of the glans, there is little evidence for this and studies are inconsistent.] Fink "et al." reported " [a] lthough many have speculated about the effect of a foreskin on sexual function, the current state of knowledge is based on anecdote rather than scientific evidence."cite journal |author=Fink KS, Carson CC, DeVellis RF |title=Adult circumcision outcomes study: effect on erectile function, penile sensitivity, sexual activity and satisfaction |journal=J. Urol. |volume=167 |issue=5 |pages=2113–6 |year=2002 |month=May |pmid=11956453 |doi= |url=http://linkinghub.elsevier.com/retrieve/pii/S0022-5347(05)65098-7] Masood "et al." state that " [c] urrently no consensus exists about the role of the foreskin or the effect circumcision has on penile sensitivity and overall sexual satisfaction."cite journal |author=Masood S, Patel HR, Himpson RC, Palmer JH, Mufti GR, Sheriff MK |title=Penile sensitivity and sexual satisfaction after circumcision: are we informing men correctly? |journal=Urol. Int. |volume=75 |issue=1 |pages=62–6 |year=2005 |pmid=16037710 |doi=10.1159/000085930 |url=http://www.cirp.org/library/sex_function/masood1/] Schoen states that " [a] necdotally, some have claimed that the foreskin is important for normal sexual activity and improves sexual sensitivity. Objective published studies over the past decade have shown no substantial difference in sexual function between circumcised and uncircumcised men." [cite journal |author=Schoen EJ |title=Should newborns be circumcised? Yes |journal=Can Fam Physician |volume=53 |issue=12 |pages=2096–8, 2100–2 |year=2007 |month=December |pmid=18077736 |doi= |url=http://www.cfp.ca/cgi/pmidlookup?view=long&pmid=18077736]
The term 'gliding action' is used in some papers to describe the way the foreskin moves during sexual intercourse. This mechanism was described by Lakshamanan & Prakash in 1980, stating that " [t] he outer layer of the prepuce in common with the skin of the shaft of the penis glides freely in a to and fro fashion..." [cite journal |title=Human prepuce: some aspects of structure and function |author=Lakshmanan S; Prakash S |journal=Indian Journal of Surgery |year=1980 |volume=44 |pages=134–137 |url=http://www.cirp.org/library/anatomy/lakshmanan/ |quote=The outer layer of the prepuce in common with the skin of the shaft of the penis glides freely in a to and fro fashion and has to be delicate and thin, as was observed in this study. [...] The inner lining of the projecting tubular part has the structure of the outer layer and adds to the thin gliding skin when retracted.] Several opponents of circumcision have argued that the gliding movement of the foreskin is important during sexual intercourse. [cite journal |author=Kigozi G, Watya S, Polis CB, "et al" |title=The effect of male circumcision on sexual satisfaction and function, results from a randomized trial of male circumcision for human immunodeficiency virus prevention, Rakai, Uganda |journal=BJU Int. |volume=101 |issue=1 |pages=65–70 |year=2008 |month=January |pmid=18086100 |doi=10.1111/j.1464-410X.2007.07369.x |quote=Opponents of circumcision, using results from selected observational studies, have argued that the procedure impairs sexual function, and reduces sexual pleasure and satisfaction through keratinization of the glans, removal of the most sensitive preputial tissues, and loss of the 'gliding' mechanism provided by the foreskin |doi_brokendate=2008-06-26] Warren & Bigelow claim that gliding action would help to reduce vaginal dryness and that restoration of the gliding action is an important advantage of
foreskin restoration. [cite journal |title=The case against circumcision |author=Warren, J; Bigelow J |url=http://www.cirp.org/library/general/warren2/ |journal=Br J Sex Med |date=Sep/Oct 1994 |pages=6–8] O'Hara describes the gliding action, stating that it reduces friction during sexual intercourse, and suggesting that it adds "immeasurably to the comfort and pleasure of both parties". [cite book |title=Sex as Nature Intended It: The Most Important Thing You Need to Know about Making Love, but No One Could Tell You Until Now |author=O'Hara K |pages=72 |year=2002 |publisher=Turning Point Publications |quote=During intercourse, the natural penis shaft actually glides within its own shaft skin covering. This minimizes friction to the vaginal walls and opening, and to the shaft skin itself, adding immeasurably to the comfort and pleasure of both parties. Friction is not entirely eliminated during natural intercourse but it is largely eliminated. Friction can take place in the lower vagina, but only if the man uses a stroke that exceeds the (forward and backward) gliding range of the shaft's extra skin. And in such a case, there will be friction only to the extent that the shaft exceeded its extra skin, which is uncommon since the natural penis has a propensity for short strokes. Primarily, it is the penis head that makes frictional contact with the vaginal walls, usually in the upper vagina where there is ample lubrication. [...] The gliding principle of natural intercourse is a two-way street—the vagina glides on the shaft skin while the shaft skin massages the penis shaft as it glides over it.] Taylor suggests that the gliding action, where it occurs, may stimulate the nerves of the ridged band[cite journal |title=Back and Forth |author=Taylor, J |journal=Pediatrics News |volume=34 |number=10 |year=2000 |pages=50 |url=http://www.cirp.org/library/anatomy/taylor2/] , and speculates that the stretching of the frenulum by the rearward gliding action during penetration triggers ejaculation. [cite journal |author=Taylor JR |title=Evidence sketchy on circumcision and cervical cancer link |journal=Can Fam Physician |volume=49 |issue= |pages=1592 |year=2003 |month=December |pmid=14708921 |doi= |url=http://www.cfp.ca/cgi/pmidlookup?view=long&pmid=14708921]
Taves used a single subject to test the actual force required to penetrate a measuring apparatus. When the foreskin was retracted a more than tenfold increase in force was needed. [cite journal |author=Taves D |title=The intromission function of the foreskin |journal=Med. Hypotheses |volume=59 |issue=2 |pages=180–2 |year=2002 |month=August |pmid=12208206 |doi= |url=http://linkinghub.elsevier.com/retrieve/pii/S0306987702002505 ] He argued that this confirms the belief of Morgan (1967) that the foreskin makes sexual penetration easier during sexual intercourse. [cite journal |author=Morgan WK |title="Penile plunder" |journal=Med. J. Aust. |volume=1 |issue=21 |pages=1102–3 |year=1967 |month=May |pmid=4226264 |doi= |url=http://www.cirp.org/library/general/morgan2/] Whiddon (1953) and Foley (1966) also believed that the presence of the foreskin made sexual penetration easier. [cite journal |author=WHIDDON D |title=I. Should baby be circumcised? |journal=Lancet |volume=265 |issue=6781 |pages=337–8 |year=1953 |month=August |pmid=13085774 |doi= |url=http://www.cirp.org/library/general/widdicombe/] [ [http://www.cirp.org/news/1966.07_Foley/ The Unkindest Cut of All ] ]
Gairdner (1949) states that the foreskin protects the glans but some studies show that inflammation of the glans is more common when the foreskin is present. [ [http://pediatrics.aappublications.org/cgi/eletters/81/4/537#1382 Balanitis and the uncircumcised male] ]
The fold of the prepuce maintains sub-preputial wetness, which mixes with exfoliated skin to form
smegma. Some authors believe that smegma contains antibacterial enzymes, [ [http://www.cirp.org/library/disease/STD/fleiss3/ Immunological Functions of the Human Prepuce] ] though their theory has been challenged. [ [http://sti.bmjjournals.com/cgi/eletters/74/5/364#112 STI -- eLetters for Fleiss et al., 74 (5) 364-367] ] The American Academy of Pediatricsstate that "No controlled scientific data are available regarding differing immune function in a penis with or without a foreskin." [cite journal |author= |title=Circumcision policy statement. American Academy of Pediatrics. Task Force on Circumcision |journal=Pediatrics |volume=103 |issue=3 |pages=686–93 |year=1999 |month=March |pmid=10049981 |doi= |url=http://pediatrics.aappublications.org/cgi/pmidlookup?view=long&pmid=10049981] Inferior hygiene has been associated with balanitis,cite journal |author=O'Farrell N, Quigley M, Fox P |title=Association between the intact foreskin and inferior standards of male genital hygiene behaviour: a cross-sectional study |journal=Int J STD AIDS |volume=16 |issue=8 |pages=556–9 |year=2005 |pmid=16105191 |doi=10.1258/0956462054679151] though excessive washing can cause non-specific dermatitis. [ [http://www.cirp.org/library/disease/balanitis/birley/ Birley: Management of Recurrent Balanitis] ]
Frenulum breveis where the frenulum is insufficiently long to allow the foreskin to fully retract, which may lead to discomfort during intercourse. The frenulum may also tear during intercourse. Phimosisis a condition when the foreskin of an adult cannot be retracted properly. (Before adulthood, the foreskin may still be separating from the glans. [ [http://www.cirp.org/library/normal/kayaba/ Kayaba: Normal Development of the Prepuce] ] ) Phimosis can be treated by gently stretching the foreskin, by changing masturbation habits, [ [http://www.cirp.org/library/treatment/phimosis/beauge2/ The causes of adolescent phimosis] ] using topical steroidointments, preputioplasty, or by circumcision.
Non-retractable foreskin is not always indicative of a clinical condition. The first time the foreskin retracts (say during
masturbationor sex) can be a slightly painful experience as the glans penisis not used to friction and air contact. However the problem resolves itself after a few days of acclimatization, which may include consciously retracting the foreskin and exposing it to air, water or friction.
A condition called
paraphimosismay occur if a tight foreskin becomes trapped behind the glans and swells as a restrictive ring. This can cut off the blood supply, resulting in ischaemiaof the glans penis. Aposthiais a rare condition in which the foreskin is not present at birth.
urgical and other modifications of the foreskin
Circumcision" is the removal of the foreskin, either partially or completely. It may be done for religious, aesthetic, health, or hygiene reasons, or to treat disease.
Preputioplasty" is a procedure to relieve a tight foreskin without resorting to circumcision.
Other practices include genital piercings involving the foreskin and slitting the foreskin. [ [http://www.emedicine.com/med/topic2874.htm eMedicine - Paraphimosis : Article by Jong M Choe, MD, FACS] ]
Langerhans cells are immature dendritic cells that are found in all areas of the penile epithelium,cite journal |author=McCoombe SG, Short RV |title=Potential HIV-1 target cells in the human penis |journal=AIDS |volume=20 |issue=11 |pages=1491–5 |year=2006 |pmid=16847403 |doi=10.1097/01.aids.0000237364.11123.98] but are most superficial in the inner surface of the foreskin.cite journal |author=McCoombe SG, Short RV |title=Potential HIV-1 target cells in the human penis |journal=AIDS |volume=20 |issue=11 |pages=1491–5 |year=2006 |pmid=16847403 |doi=10.1097/01.aids.0000237364.11123.98] The recent Szabo and Short (2000) study targets Langerhans cells as receptors of HIV, and states that these cells "must be regarded as the most probable sites for viral entry in primary HIV infection in men."cite web |url=http://www.pubmedcentral.gov/articlerender.fcgi?artid=1127372 |title=How does male circumcision protect against HIV infection? |accessdate=2007-11-30 |format= |work=] Langerhans cells are also known to express the c-type lectin langerin, which may play a role in transmission of HIV to nearby lymph nodes.cite journal |author=McCoombe SG, Short RV |title=Potential HIV-1 target cells in the human penis |journal=AIDS |volume=20 |issue=11 |pages=1491–5 |year=2006 |pmid=16847403 |doi=10.1097/01.aids.0000237364.11123.98] However, de Witte "et al." (2007) reported that langerin, produced by Langerhans cells, blocks the transmission of HIV to T cells.cite journal |author=de Witte L, Nabatov A, Pion M, "et al" |title=Langerin is a natural barrier to HIV-1 transmission by Langerhans cells |journal=Nat. Med. |volume=13 |issue=3 |pages=367–71 |year=2007 |pmid=17334373 |doi=10.1038/nm1541]
Foreskin in non-human species
koalas the foreskin contains naturally occurring bacteria that play an important role in fertilization. [ [http://www.uq.edu.au/news/?article=2193 UQ researchers unlock another koala secret] ] Almost all mammals have foreskins, although in these non-human cases the foreskin is usually a sheath into which the whole penis is retracted. Only monotremes(the platypus and the echidna) lack foreskins. [cite encyclopedia |url=http://encarta.msn.com/encyclopedia_761553537_2/Reproductive_System.html |year=2006 |title=Reproductive System |encyclopedia=MSN Encarta |publisher=Microsoft Corporation |location=Seattle, WA, USA]
Foreskin-based medical and consumer products
Foreskins obtained from circumcision procedures are frequently used by biochemical and micro-anatomical researchers to study the structure and proteins of human skin. In particular, foreskins obtained from newborns have been found to be useful in the manufacturing of more human skin. [cite news |first=Robin |last=McKie |title=Foreskins for Skin Grafts |work=The Toronto Star |date=1999-04-04 |accessdate=2008-05-19]
Foreskins from circumcised babies are used to make a commercial anti-wrinkle skin cream. A six-week supply costs US$130. [cite web |url=http://www.nbc10.com/health/1808693/detail.html |title=The Skinny On 'Miracle' Wrinkle Cream|year=2002|month=November|publisher=NBC Universal, Inc|work=NBC10.com|accessdate=2008-08-20]
Foreskins of babies are also used for
skin grafttissue, [cite web|url=http://www.wired.com/science/discoveries/news/1999/02/17912|title=High-Tech Skinny on Skin Grafts|date=02.16.99|publisher=CondéNet, Inc|work=www.wired.com:science:discoveries|accessdate=2008-08-20] [cite web|url=http://www.emedicine.com/derm/TOPIC867.HTM|title=Skin Grafting|publisher=WebMD|work=www.emedicine.com|accessdate=2008-08-20] [cite web|first=Catherine|last=Amst|coauthors=Carey, John|url=http://www.businessweek.com/1998/30/b3588001.htm|title=Biotech Bodies|date=July 27, '98|publisher=The McGraw-Hill Companies Inc|work=www.businessweek.com|accessdate=2008-08-20] and for β-interferon-based drugs. [cite web |author=Cowan, Alison Leigh|url=http://query.nytimes.com/gst/fullpage.html?res=9E0CE6D81E38F93AA25757C0A964958260&partner |title=Wall Street; A Swiss Firm Makes Babies Its Bet|date=April 19, 1992|publisher=New York Times|work=New York Times:Business|accessdate=2008-08-20]
fibroblastshave been used in biomedical research. [cite journal |last=Hovatta |first=O. |coauthors=M. Mikkola1, K. Gertow, A.-M. Strömberg, J. Inzunza1, J. Hreinsson1, B. Rozell, E. Elisabeth Blennow, M. Andäng, L. Ährlund-Richter |year=2003 |month=July |title=A culture system using human foreskin fibroblasts as feeder cells allows production of human embryonic stem cells |journal=Human Reproduction |volume=18 |issue=7 |pages=1404-1409 |pmid=12832363 |url= ]
Forcible retraction of the foreskin
* [http://www.prepuce.com Prepuce.com - An Erotic View Point and many images of user self contributed foreskin]
* [http://www.foreskin.org Foreskin.org - Many detailed pictures of the human male foreskin]
* Lakshmanan S., Prakash S. [http://www.cirp.org/library/anatomy/lakshmanan/ Human prepuce: some aspects of structure and function] . "Indian J Surg" 1980;44:134-7.
* Davenport M. [http://bmj.bmjjournals.com/cgi/content/full/312/7026/299 Problems with the penis and prepuce] . "British Medical Journal" 1996;312:299-301.
* Simpson ET, Barraclough P. [http://www.cirp.org/library/hygiene/simpson1/ The management of the paediatric foreskin] . "Aust Fam Physician" 1998;27(5):381-3.
* Cold CJ, McGrath KA. [http://www.cirp.org/library/anatomy/cold-mcgrath Anatomy and histology of the penile and clitoral prepuce in primates] . "Male and Female Circumcision" 1999
* Peter Charles Remondino. " [http://www.gutenberg.org/etext/23135 History of Circumcision from the Earliest Times to the Present] ." Philadelphia and London; F. A. Davis; 1891.
* Video "The Prepuce" a film prepared by Doctors Opposing Circumcision for medical students.::(WMP, streaming) http://www.doctorsopposingcircumcision.org/video/prepuce.html::(WMP, download) http://www.doctorsopposingcircumcision.org/video/Circumcision_WM7NTSC_256k_D.wmv
* - "The Male Perineum and the Penis: The Surface Anatomy of the Penis"
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