Below: This photograph shows the lack of skin mobility during erection of a circumcised penis. Note the dark scar where the foreskin was amputated.

This tightness and the unnatural dryness of the penile shaft and head causes some men (and their partners) pain, abrasion, and bleeding during sex. Breaks in the skin are an effective way to transmit and contract sexually transmitted diseases, including HIV.

Below: These five photographs show how the shaft skin of
an intact (non-circumcised) penis moves during sexual activity.

 
Anonymous photo taken from usenet news.

Range of skin movement marked by point A is several inches back and forth.
Note how point B moves and the end of the foreskin widens to accommodate
the head of the penis. Notice the smooth texture of the head of the penis.
The moist mucosal surface of the foreskin and glans is similar to that
of the female labia and vagina.
NOTE: Retraction is normally not possible or desirable in infants and young children.

The glans (penile head) is normally an internal organ protected by the moist mucosal tissue of the prepuce (foreskin). Without the foreskin, the glans is exposed to the outer environment (air, soap, clothing, sun, etc.). The glans dries out and develops several extra layers of skin (keratinization).¹ Compare the dry, cracked appearance of the glans of a circumcised penis (upper right) with the moist mucosal end of the glans of an intact penis (lower right). The unnatural dryness of the circumcised penis can cause abrasion and bleeding during sex, whereas the moistness of the intact penis makes sex more comfortable, especially during penetration. For women with circumcised male partners, the problem of 'vaginal dryness' during sex may also be partly attributable to the unnatural dryness of the circumcised penis.

Besides removing the densely nerve-laden foreskin, circumcision removes 50% of the penile shaft skin and associated nerve endings.² The exposed glans then keratinizes, causing further loss of sensation. Many circumcised men in the Awakenings survey³ reported that desensitization caused them to abandon or bypass the subtler pleasures of genital foreplay in favor of immediate intercourse, which would offer them greater stimulation. They often hurried through intercourse, however — often needing extraordinary and sometimes violent thrusting — to obtain sufficient stimulation for both pleasure and orgasm. Other men reported frequent reliance on behaviors offering more stimulation than vaginal sex (e.g., oral sex, anal sex or masturbation) or compensating for diminished quality of sexual response with quantity (sexual compulsivity).

Eventually, keratinization occurs even after adult circumcision. It can also occur in intact men with short foreskins or those who habitually wear their foreskin in the retracted position.

Imagine how different female sexual response would be if the clitoral hood (female foreskin) and the labia were removed. Exposure of the clitoris to the constant effects of the outer environment would approximate the effects of male circumcision.

Circumcised penis
(top view)

Intact penis
(end view)

The frenulum is a web of tissue connecting the foreskin to the underside of the glans (similar to the frenulum under the tongue or the upper lip). The penile frenulum is densely nerve-laden and is described as a male 'G-spot' — a very erogenous part of the penis.⁴ Circumcision often destroys the frenulum. Left: Circumcised penis with no frenulum. Right: Intact penis with retracted foreskin and an intact frenulum.

Image: Pro-Foreskin Site

The pigmentation of the epidermal tissue of the penile shaft is often different from that of the mucosal tissue of the glans and inner foreskin. In the intact penis, only the epidermal tissue of the penile shaft and outer foreskin are visible. The pigmentation of this tissue is usually consistent. Only when the foreskin is retracted, and the glans is exposed, does any pigmentation difference become noticeable.

In a circumcised penis, any difference in pigmentation (between the epidermal tissue and that of the mucosal tissue of the glans and remaining inner foreskin) is readily and permanently visible. Stark contrasts in skin tone can be a source of embarrassment and self-esteem issues for some circumcised males.

Separation of the foreskin from the glans occurs naturally between birth and age 18, which is why forcible separation is not required for adult circumcision. Infant circumcision involves the forced separation of these structures, which can tear portions of the glans that are tightly adhered to the foreskin. Also, some circumcision devices (e.g., Sheldon clamp) can sever all or part of the glans, or fail to shield the glans from the scalpel used to remove the foreskin.