These structures are protected from the irritating and damaging effects of faeces, urine and even nappies. The foreskin has very sensitive nerve endings in it. These enhance sexual pleasure. During sexual intercourse the foreskin protects from chafing and provides a moveable sheath that allows easy sliding of the penis in the vagina. It protects the glans from trauma throughout life.
Circumcision is done for religious and cultural reasons.
In phimosis the opening at the end of the foreskin is so small that the foreskin cannot be retracted. There are no good medical reasons for routine circumcision. If the male practices good hygiene, the reasons that used to be given for the routine practice of circumcision fall away. This substance is called smegma. Smegma is a natural secretion that occurs under the foreskin.