foreskin

Eva Rudolf-Müller is a freelance writer in the medical team. She studied human medicine and newspaper sciences and has repeatedly worked in both areas - as a doctor in the clinic, as a reviewer, and as a medical journalist for various specialist journals. She is currently working in online journalism, where a wide range of medicine is offered to everyone.

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The foreskin (preputium) is a double layer of skin that covers the glans penis. Since the penis is greatly elongated during an erection, a reserve skin fold is required that withdraws from the glans. On the underside of the penis, the preputium is attached to the glans via the foreskin ligament (frenulum preputii). Read everything you need to know about the foreskin!

What is the foreskin?

The foreskin (prepuce) is a double layer of skin. It represents the end of the elastic and easily movable skin that envelops the shaft of the penis. On the underside of the glans, the foreskin is attached to the glans by the foreskin ligament (frenulum).

The inner sheet of the foreskin has a mucosal-like function. A whitish-yellowish, sebum-like mass, the smegma, is formed from the secretion of the sebum glands and flaked skin cells of the prepuce. It also contains bacteria, including what is known as the smegma bacterium (Mycobacterium smegmatis).

The foreskin in childhood

Up to the first year of life, the foreskin can only be pulled back over the glans in about half of the boys; by the end of the second year, this is already possible in 80 percent of the boys. Until the age of three, it is still normal for the prepuce to be stuck to the glans and not to be able to be withdrawn. However, by the onset of puberty, the foreskin is loosened in most cases and can be pushed back.

What is the function of the foreskin?

When the penis is slack, the foreskin is protective over the glans. During an erection, the double skin layer serves as a reserve skin fold: When the limb becomes stiff and elongates, the prepuce retracts over the glans.

Where is the foreskin located?

The prepuce, which is normally easily movable, is located at the tip of the penis and covers the glans here.

What problems can the foreskin cause?

If the foreskin is too tight and cannot be pulled back over the glans, it is called phimosis. The smegma can then not be removed or can only be removed with great difficulty, which can lead to inflammation (balanitis = glans inflammation). Phimosis can be congenital or develop later, for example due to inflammation, shrinkage or thickening of the foreskin frenulum.

Attempts to pull the foreskin back too early in childhood can cause the smallest injuries that heal with scarring.

The foreskin ligament can also be congenitally too short (frenulum breve) and then tear during an erection.

If a foreskin that is too tight is forcibly pulled back over the glans into the ring-shaped furrow behind it (corona glandis), the glans can be pinched off. This so-called paraphimosis should be treated medically as soon as possible because the glans tissue can die off due to the interrupted blood flow.

In the case of poor personal hygiene, the bacteria that the smegma contains can lead to inflammation. When the smegma hardens, concrements (balanoliths) form together with uric salts.

A tumor of the foreskin is just as possible as a malignant melanoma (black skin cancer) in this area.

Tags:  healthy feet prevention menshealth