How did the practice start?
The Egyptians were removing the foreskins of young boys as early as 2400 B.C., but the origins of circumcision remain a mystery. "It's like asking the question, 'Where did religion come from?'" said medical historian David L. Gollaher. Jews have performed the ritual on 8-day-old boys for at least 3,000 years, in accordance with God's commandment to Abraham that circumcising "the flesh of your foreskins...shall be a sign of the covenant between me and you." Muslims consider circumcision a purification ritual that can be performed on males of any age, and some African societies initiate pubescent boys into manhood through a circumcision ritual that tests their ability to withstand pain. For Americans, starting in the late 19th century, circumcision was touted as a cure for nervousness, masturbation, and imbecility. It remains a routine procedure in the U.S., with more than half of all boys circumcised — far more than in Europe.

Does the operation have real health benefits?
Three recent large-scale studies of African men have found that circumcision markedly lowers the risk of infection with HIV, the virus that causes AIDS; it also reduces infection from other sexually transmitted diseases, including the cancer-causing human papillomavirus (HPV). Researchers say that's because the foreskin can develop microscopic tears during sexual activity, allowing infections to more easily reach the bloodstream. Circumcision has also been found to reduce the risk of urinary-tract infections in a baby's first year. Citing those studies, the American Academy of Pediatrics in August shifted its previously neutral stance on circumcision and announced that the procedure has "significant" health benefits. For every 909 circumcisions, the pediatricians reported, one man will be spared a diagnosis of penile cancer.

So why do some people oppose it?
Many frame their opposition to circumcision as a human rights issue: They see removing a healthy part of a newborn's body without his consent as an involuntary form of "mutilation" — a violation of medical ethics. "Babies should be left alone," said Georganne Chapin of the anti-circumcision group Intact America. "When they become men, they can make their own informed decision about whether they want to remove a part of their own penises." Chapin and other so-called "intactivists" dispute the evidence of circumcision's medical benefits — infections can be prevented with proper hygiene and condoms, they claim — and point to the pain involved and the risks of bleeding, infection, and other complications. Some critics also maintain that circumcision makes the penis less sensitive, robbing men of the full range of sexual pleasure. Intactivists seek to change society's attitudes about the operation, with the goal, according to movement leader Matthew Hess, of "making cutting boys' foreskin a federal crime."

Have they made progress?
The procedure is definitely becoming less prevalent. Rates of hospital circumcision in the U.S. have dropped from a high of about 79 percent in the 1970s to 55 percent in 2010, according to the Centers for Disease Control and Prevention. That may be partly because Medicaid has stopped paying for the surgery in 18 states; some insurance companies also have stopped covering it. In addition, Latin American immigrants tend not to circumcise. But another reason for the decline is that the moral argument against circumcision is swaying many American parents. In San Francisco last year, 12,000 citizens supported a ballot initiative that would have made circumcision a misdemeanor punishable by a fine of up to $1,000 or a year in jail. A judge blocked the referendum on a technicality, but the ban's sponsor, Lloyd Schofield, claimed victory. "Just getting people to think and discuss this is very rewarding," he said. And this year in Cologne, Germany, a regional court ruled that the botched ritual circumcision of a 4-year-old Muslim boy amounted to assault, and the German Medical Association counseled doctors to stop performing the operation.

How have religions responded?
Across Germany, furious protests by religious Jews and Muslims prompted lawmakers to draft a law making circumcision explicitly legal, as long as it is carried out by trained experts and parents are informed of medical risks. A similar clash ignited this summer in New York City, after city health officials found that in the last decade, 11 baby boys there had contracted herpes infections — and two of them had died — through a rare Orthodox Jewish rite called metzitzah b'peh, in which the mohel who performs ritual circumcision sucks the blood directly from the fresh wound. The city's Board of Health proposed making parents sign a form laying out the medical risks, but ultra-Orthodox Jewish leaders vowed to defy the order and last week won a temporary injunction. New parents not bound by religious custom, meanwhile, are facing the circumcision decision with considerable doubt and confusion. Circumcision "does have a medical benefit," says Dr. Doug Diekema, who took part in the American Academy of Pediatrics task force on the procedure. "Not everyone would trade that foreskin for that medical benefit. It's a hard decision, and there are good reasons for almost any decision you want to make."

The life of a mohel
Max Mintz has circumcised more than 9,700 babies during the past 30 years and expects to hit the 10,000 mark by year's end. A retired Houston-area pediatrician, he performs the ritual for Jewish families in Texas and across the country, and will happily circumcise non-Jewish babies, too. Mintz, who charges about $350 for his services, says the procedure takes about a minute, involving a deft cut with a ritual knife called an izmel. "If you know how to do something surgically, just changing to another instrument is not so difficult," Mintz said. "And the ritual method is so much simpler." An Orthodox Jew, Mintz is gratified to be able to marry his faith with his surgical skills. And performing a bris, the Hebrew word for circumcision, is "always a very happy occasion," he said. "I don't have to do funerals like a rabbi. Everyone wants to meet you."