Keratinisation
Foreskin removal, like eyelid removal, causes a mucous membrane to dry out and become calloused or “keratinised.” Many circumcision advocates believe the keratinised penis is more effective at disease prevention than the natural mucous membrane on the basis that it appears “tougher.” However there is little scientific evidence for this viewpoint.
The photo on the left shows the glans penis in a natural state, with the foreskin retracted behind the coronal ridge to prevent vaginal scraping during outward movement (the “cushion effect”). The photo on the right shows a circumcised penis whose glans has been keratinised from long-term exposure without a foreskin.
Thicker skin from keratinisation may require thinner condoms. The Bill & Melinda Gates Foundation, a leading investor in VMMC research and implementation, has offered up to $1 million USD to develop an ultra-thin condom to “enhance the pleasure so as to increase uptake.” (NY Daily News)
Related: See our pages on mucous membranes and sexuality.