Doctors Opposing Circumcision
Genital Integrity Policy Statement
|
|
Doctors Opposing Circumcision
|
|
One must understand the nature and function of the structure that is amputated by circumcision in order to properly evaluate the effects of male circumcision. This chapter provides that information.
General Description
The prepuce traditionally has been described as a simple fold of skin,1 for which the purpose and function are unknown. This is inaccurate. In reality, the prepuce is a complex structure with multiple anatomical and physiological functions.2
The prepuce is a portion of the entire covering of the penis. It is specialized tissue, composed of skin, mucosa, nerves, blood vessels, and muscle fibers.2 It is anchored by the abdominal wall at the proximal end of the penis and at the proximal end of the glans penis. It is not attached to the shaft of the penis, so, after puberty, it is free to slide back and forth, everting and inverting as it does.3 The sliding/rolling back and forth is called the gliding action.3,4
A frenulum is found on the ventral side of the penis. The frenulum serves to tether a movable structure to a non-movable structure. The penile frenulum returns the foreskin to its normal protective forward position.2 Most men report that the frenulum is highly erogenous tissue.
Peripenic Muscle
In the skin of the penis, there is a sheath of dartos fascia muscle fibers — the peripenic muscle.2,3,5 The muscle fibers keep the prepuce snug against the glans penis.3 The fibers of the peripenic muscle sheath form a whorl at the tip of the prepuce, which act as a sphincter,3 especially in infants and children. The sphincter also serves to prevent inadvertent retraction of the prepuce. The peripenic muscle gives the prepuce great elasticity, allows it to stretch, and helps to return the prepuce to its forward, protective position after retraction.2 The elasticity of the prepuce plays an important role in the erogenous and sexual functions of the prepuce.
Immunology
The prepuce covers and protects the glans penis and urinary meatus. In most males, the prepuce protects the sterile urinary tract environment in infancy and maintains the moistness — beneficial to good health — of the mucosal surface of the glans penis throughout life.6 Fleiss et al. (1998) have identified immunological functions that help to protect the body from pathogens:7
The epidermis of the prepuce contains Langerhans cells that secrete cytokines,2 hormone-like low-molecular-weight proteins, which regulate the intensity and duration of immune responses.9 de Witte and colleagues (2007) report that the Langerhans cells produce langerin, a substance that provides a barrier to HIV infection.10
Innervation
The prepuce of the newborn male has extensive innervation. Winkelmann (1956) reported, “[t]he principal form of innervation of human newborn prepuce consists of a deep and superficial network of nerve fibres in the dermis.”11 Moldwin & Valderrama (1989) reported an extensive neuronal network in the prepuce.12
The prepuce of adult males is even more extensively innervated. Winkelmann (1959) described the prepuce as a specific erogenous zone with nerves arranged near the surface in rete ridges.13 Taylor et al. (1996) also found nerves near the surface in rete ridges and further described a concentration of nerve endings in a ring of ridged tissue just inside the tip of the prepuce near the mucocutaneous boundary, which he named the ridged band.14 The nerve endings in the ridged band are Meissner's corpuscles and Krause's end-bulbs.
The nerves of the penis, including the preputial nerves, supply sensory input to both the somatosensory and autonomic nervous systems by different routes.2 The sensory input to the somatosensory nervous system is supplied through the dorsal nerve of the penis, and the autonomic nervous system is supplied through the parasympathetic nerves, which run adjacent to and through the wall of the membranous urethra.
The prepuce is provided with an extensive vascular network to bring oxygen to support the heavy innervation.2,7,14
Several writers have commented on the sensitivity of the prepuce. Winkelmann (1956) wrote, “…it is a region of great sensitivity and possessed of an abundant nerve supply,”11 and later (1959) identified the prepuce as a specific erogenous zone.13 Falliers (1970) noted the “sensory pleasure associated with tactile stimulation of the foreskin.”15 A landmark study by Sorrells et al. (2007) of the fine-touch sensitivity of the penis finds that the areas most sensitive to fine touch are on the foreskin.16 Circumcision, therefore, amputates the most sensitive areas of the penis.
Sexual Function
The prepuce is primary, erogenous tissue necessary for normal sexual function.2 In adult life, the gliding action facilitates introitus4 and reduces friction and chafing during coitus.5 The movement and stretching of the prepuce during coitus stimulate the nerve endings in the prepuce, produce erogenous sensation, and eventually ejaculation.18,19 The presence of the prepuce tends to protect the corona of the glans penis from direct stimulation, helps to prevent premature ejaculation20,21 and contributes to female satisfaction.22 (See Chapter Six for a discussion of the sexual harm of prepuce excision.)
Natural Development
The great majority of newborn infant boys are born with the inner surface of the prepuce fused with the glans.2 In addition, the tip of the prepuce at birth usually is too narrow to allow retraction. The duration of these conditions vary with the individual but can last until the completion of puberty or longer. For these two reasons, the non-retractile foreskin is normal in childhood and adolescence and cannot be considered a disease requiring treatment.
The first data on development of the retractile prepuce was provided in 1949 by British pediatrician Douglas Gairdner.22 Gairdner said 80 percent of boys have a retractable foreskin by the age of two years, and 90 percent of boys have a retractable prepuce by the age three. His erroneous information23 has been incorporated into medical textbooks and medical school curricula for decades, and it still is repeated in medical literature today.24
Gairdner’s data are inaccurate23-25 and, unfortunately, most healthcare providers have been taught this inaccurate information,24,25 which contributes to improper diagnosis of “pathological phimosis” in the healthy, normal, non-retractile foreskin. Retractability usually occurs much later than previously believed.2,24,25 About 44 percent of boys have a fully retractable prepuce by age 10-112,27,28,29 and about 95 percent have a fully retractable prepuce by age 18.2,27 Non-retractile foreskin is the more common condition until 10-11 years of age. Thorvaldsen & Meyhoff (2005) report that the mean age of first foreskin retraction is 10.4 years.29 Non-retractile foreskin in childhood and adolescence is not a disease and does not require treatment.
Ballooning of the prepuce in childhood during urination is harmless and self-limiting. Babu et al. (2004) have shown that ballooning does not cause obstructed voiding.30 Ballooning disappears with increasing maturity. No treatment is required.31
References
