Foreskin
In mammals, the foreskin or prepuce is the retractable double-layered fold of skin and mucous membrane that covers the head of the penis, (the glans penis). It serves as a sheath to protect the glans penis from injury.
The human foreskin
In humans, the foreskin, a part of the penis, is a double-folded tube of skin and mucous membrane [1] (similar to the inside of the mouth) which attaches at the crested end of the glans at the sulcus, and to the body above the pubic bone and scrotum. Unlike the skin on the rest of the body, which is attached to the underlying tissue, the foreskin and shaft skin are free to glide along the shaft of the penis. Smooth muscle fibres keep the foreskin close to the glans penis but make it highly elastic.[2]
The inner surface of the foreskin is usually fused with the glans penis at birth.[3] The fusion gradually breaks down over a period of up to 17 years, releasing the foreskin and allowing it to become retractable.[4] 44 percent of boys have fully retractable foreskins by age ten, 90 percent by age 16, and 99 percent by age 18.
The coverage of the glans by the foreskin in adults is a highly variable characteristic. Some men have abundant overhang when flaccid, while others do not have complete glans coverage. Schoeberlein, in a German study, found that around 50% of uncircumcised young men had full coverage of the glans while 42% had partial coverage while the remaining 8% were both glans and sulcus free. After adjusting for circumcision he established that in 4% of the young men the foreskin atrophied (shrank) spontaneously.
Hygiene
One of the purposes of the foreskin is to protect the glans of the penis from damage. The removal of the foreskin is known to reduce pathogenic bacteria[5] [6], as well as reducing urinary tract infections. Only the outside of the foreskin should be washed during infancy and childhood. It is entirely normal for the foreskin to be fused with the glans in babies and not to fully retract in young boys. Forcible retraction of the foreskin should be avoided and the child himself should be the first person to retract the foreskin.[7] Premature retraction, which is painful, can cause infection.
Regular washing under the foreskin becomes important once the foreskin becomes retractable. If the man does not wash under the foreskin regulary, the accumulation of secretions, sloughed skin cells, nectrotic debris and bacteria produce a white creamy paste between the prepuce and glans penis called smegma which if allowed to accumulate in the foreskin cavity can exude an unpleasant odour. [8] Inability to retract and wash under the foreskin has been implicated in penile cancer [9]. In developing countries where infant circumcision is not routinely practised and genital hygiene is poor, penile cancer may comprise 10 to 20% of all malignancies, although it is rare in Western countries. Squamous cell carcinoma of the penis
In its policy statement on circumcision the American Academy of Pediatrics says, "Circumcision has been suggested as an effective method of maintaining penile hygiene since the time of the Egyptian dynasties, but there is little evidence to affirm the association between circumcision status and optimal penile hygiene ... In one study, appropriate hygiene decreased significantly the incidence of phimosis, adhesions, and inflammation, but did not eliminate all problems."[10]
Conditions
Phimosis is a condition, usually considered abnormal in an adult, in which the foreskin cannot be retracted fully or at all. Phimosis is treated through the use of topical steroid ointments, stretching, or circumcision. In some cases, a dorsal slit is made in the foreskin to correct a medical problem. See phimosis for more information on treatment of phimosis. Non-retractile foreskin is a normal condition prior to puberty. [11]
Where the foreskin is partially retractable, a condition called paraphimosis may occur where the foreskin becomes trapped behind the glans. This is a serious condition which must be treated as a medical emergency.
Surgical modification
In addition to its use as a treatment for phimosis, circumcision is also practiced, primarily on infants, for religious or aesthetic reasons or alleged health benefits.
Preputioplasty is now the preferred surgical treatment for non-retractile foreskin among some surgeons.[12] [13]
Religious and Cultural Views
Both Jews and Moslems, in most interpretations of religious doctrine, practice ritual circumcision whereby the foreskin of a young boy is cut away permanently. In Judaism, an expert circumcisor known as a mohel performs the ritual, known as brit milah on an eight day old baby boy. It is considered to be religiously mandated by the Torah as the mark of the Covenant between God and Abraham, the forefather of both the ancient Hebrews, and the sons of Ishmael. The purported foreskin of Jesus Christ has been venerated as a Christian relic in various places at various times. It is known as the Holy Prepuce.
Many infant circumcisions, particularly in the United States, are carried out without a context of religion. As adults, some men undergo circumcision for comfort, appearance, or a sense of completion. Other men may choose foreskin restoration for similar reasons, which provides a man with a replacement of the lost foreskin, usually by non-surgical tissue expansion techniques.
See also
External links
- Anatomy and Functions of the Male Foreskin by Marilyn F. Milos, R.N. and Donna Macris, C.N.M.; (1994) includes photos and animations. Note: The website is strongly anti-circumcision.
- Fleiss P, Hodges F, Van Howe RS. Sex. Trans. Inf. 74(5): 364-367 (1998). Immunological functions of the human prepuce Note: the authors hold a strong anti-circumcision point of view.
- C.J. Cold and J.R. Taylor. British Journal of Urology 83, Suppl. 1: 34-44 (1999) The Prepuce Note: the authors hold a strong anti-circumcision point of view.