Controversial new research casts doubt on the long-held belief that circumcision reduces sexual sensitivity for men who have undergone the procedure.
Circumcision, a procedure performed throughout history — for reasons ranging from the fulfillment of a biblical covenant to a means of curbing masturbation — has received both praise by those who tout its supposed medical benefits and scorn from those who claim it has traumatic aftereffects.
Now, in a Canadian study appearing in the most recent issue of the Journal of Sexual Medicine, researchers found that the glans, or head of the penis, is just as sensitive on a circumcised man as on an uncircumcised one.
"It's probably the best study I've seen of this kind of work," said June Reinisch, the former director of the Kinsey Institute. Reinisch was not involved with the study.
Reinisch praised the study for using the best available technology, for matching circumcised and uncircumcised subjects on a number of important factors and for taking measurements where subjects were in an aroused state — something not done in previous studies.
"It's the state in which we're all interested," said Reinisch. "We're not interested in how [men] feel when they hold themselves when they pee."
Still, the benefits of circumcision remain controversial. Research in recent years has suggested circumcision might benefit men by lowering their risk for AIDS and other STDs. Other studies suggest that the procedure may limit the risk of passing the cancer-causing human papilloma virus (HPV) onto female partners, although the merit of those studies has been disputed.
The American Academy of Pediatrics reflects that doubt in its official policy, which states: "Existing scientific evidence demonstrates potential medical benefits of newborn male circumcision; however, these data are not sufficient to recommend routine neonatal circumcision."
In order to test the sensitivity of the penis, researchers had men disrobe and watch an erotic film. Cameras were used to measure the men's arousal.
Once aroused, researchers pressed increasingly firmer filaments against the erect penises until the subjects indicated they felt the touch, and then at the point where they felt pain.
In addition to comparable sensitivity between circumcised and uncircumcised men, the study also showed that the penis becomes less sensitive when aroused.
"When God invented sexual activity, the arousal response is actually a form of anesthesia," said Irwin Goldstein, editor of the Journal of Sexual Medicine.
"It actually makes more sense when you think of it that way," he said, explaining that if the penis became more sensitive, it might limit sexual activity and, therefore, reproduction.
While psychologist Kimberley Payne, one of the study's authors, said the research seems to refute the idea that the foreskin keeps the penis sensitive, she was hesitant to draw a broader conclusion from her study.
"This just scratched the surface, and there is so much more to look at," she said.
She said ultimately she hoped someone would be able to measure the full range of sexual sensation in circumcised and uncircumcised men during sex, but was unsure how that would be done.