Circumcise This!How to remove a full-grown foreskin.

By Daniel Engber
Posted Friday, Dec. 15, 2006, at 6:21 PM ET

Note: Some links in this article go to Web sites containing graphic images of the medical procedures described. These images might not be appropriate for viewing at the workplace.

Adult circumcision can reduce the risk of HIV transmission by 50 percent, the National Institutes of Health reported on Wednesday. International health groups are considering how to apply the new findings, and the government of South Africa may institute a national circumcision policy. How do you circumcise an adult?

Very carefully. First, doctors inject some painkillers into the two nerves that connect into the base of the penis. (They might add a few more injections around the circumference of the shaft, to create what's called a "ring block.") Once the penis is good and numb, it's possible to gently detach the inside of the foreskin from the shaft by pushing a blunt probe between the two. Then it's time for the snipping.

The easiest way to do this is to use the "guided forceps" technique. In this procedure, the foreskin is grabbed and pulled forward over the head of the penis—called the glans—and clamped straight across with a long forceps. Now it's a cinch to cut the skin along the outside edge of the forceps, in much the way a barber might hold a lock of hair between his fingers and snip it with a pair of scissors. The metal arm of the forceps guides the incision and protects the head of the penis from injury.

The guided forceps technique is simple to learn, but it can leave a little bit of extra foreskin around the ridge at the bottom of the glans. The "dorsal slit" approach has a cleaner outcome but can be a bit more difficult to perform. Here the foreskin is pulled forward and a slit is made along the top. With the foreskin pulled taut, dissection scissors are used to cut in a circle from the slit.

Another, more difficult technique is the "sleeve resection." This involves making two parallel, circular cuts farther down the shaft. This frees up a band of foreskin that can be dissected off of the penis, revealing a ringlike gap. The remaining portions of foreskin can be pulled together and sewn up, with very attractive results.

All of this would be much easier if doctors could circumcise adults using the same techniques they use on newborn babies. Most neonatal circumcisions are conducted with a special device that fits over and protects the head of the penis. The Gomco clamp works by pulling the foreskin over a metal cap, with the glans nestled safely inside. The doctor then screws the clamp over the cap and snips around the edge. Alternatively, the glans can be covered with a device called the PlastiBell. The foreskin is bound tightly around a plastic cap with a piece of string. The plastic remains in place until the tied-off skin withers and falls off, about a week later.

It's hard to find a Gomco clamp or PlastiBell in a size appropriate for adults, and it's not clear if they would be safe and effective. For one thing, an adult would be much more likely to pop off a PlastiBell with an involuntary erection as he recovered. (Babies get erections, too, but not nearly as often.)

However a man is circumcised, he should follow a few simple steps for postoperative care. First, he should leave the doctor's office in tight-fitting underpants, to keep his surgical dressing firmly in place. (A few days later he'll want to switch to boxers, so as not to irritate the wound.) He should avoid riding a bicycle for at least five days, and he should refrain from all masturbation or sexual intercourse for four to six weeks. (Click here for a PDF of the United Nations how-to guide for circumcision.)

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