Both the male penis and the female clitoris have very sensitive glans, which must be protected from friction and other external irritations. For both sexes, a specialized skin hood called a prepuce is designed to provide such protection. The term prepuce actually refers to both male and female genitalia, but the protective structure is often called a foreskin in males and a clitoral hood in females. Prepuces are not limited to humans, either. Many mammals also have protective flaps of skin which protect and cover their genitals from the elements or infection.
Many male babies have their foreskins removed surgically in a process called circumcision. Sometimes this procedure is performed as part of a religious rite, but other times it is performed as a hygienic procedure shortly after birth. The removal of foreskins is an ancient practice, mentioned frequently in the Old Testament as a symbol of subservience or sacrifice. In modern times, circumcisions are often performed because of a belief that an intact prepuce is unhygienic and unaesthetic. Opponents of circumcision contend that the male foreskin serves many vital functions and should remain intact. During circumcision, only the portion of the foreskin covering the glans or head of the penis is removed surgically.
The prepuce in both men and women is now believed to serve several important functions. The foreskin contains a significant number of sensitive nerves, which means the intact male prepuce would be considered an erogenous zone during sexual activity. The clitoral hood also enhances female sexual response by enveloping the clitoris during masturbation and other sexual stimulation. Both the foreskin and the clitoral hood provide a natural lubrication, which also makes such stimulation even more pleasurable. The prepuce keeps both male and female sexual organs in a state of heightened sensitivity.
There is also a hygienic element to the foreskin, especially in males. The intact foreskin protects the glans from routine chafing and irritation caused by clothing and physical activity. The small opening at the end of the foreskin allows for normal urination, and can also be retracted painlessly to expose the glans during bathing. While the end of the foreskin can indeed become infected with harmful bacteria, it is much more likely to form a substance called smegma. Smegma may develop an unpleasant odor or cheese-like appearance, but it is actually believed to contain some natural antibacterial properties. Smegma can also form under the clitoral hood as well.
The external component of the prepuce can be seen as a natural extension of the skin surrounding the penis or labia majora. The interior component of the prepuce, however, is more of a mucous membrane, similar to eyelids or the inside of the mouth. The external foreskin or clitoral hood can develop rashes or infections, most likely treated with topical medications. Occasionally the interior walls of the foreskin or clitoral hood will form preputial adhesions with the penis or clitoris, and this could require surgical intervention. If a man's foreskin cannot fully retract during sexual intercourse, the act could become very painful. Similarly, a woman could experience discomfort if the clitoral hood forms adhesions or loses its natural lubrication.
The practice of removing the foreskin or clitoral hood has become controversial in recent years, with some researching now suggesting that a male child experiences significant pain during the circumcision procedure. Removal of the female clitoral hood has also received worldwide scrutiny, although female circumcision is often confused with the complete removal of the clitoral hood and external clitoris. Some cultures still practice a ritualistic removal of both structures in order to repress a female child's natural sexual development. Other religions and cultures also view the removal of a male child's foreskin to be an honorable act of contrition or sacrifice to God.