U.S. health officials on Tuesday released a draft of long-awaited federal guidelines on circumcision, saying medical evidence supports having the procedure done. "The scientific evidence is clear that the benefits outweigh the risks," said Dr. Jonathan Mermin, of the U.S. Centers for Disease Control and Prevention, who oversees the agency's programs on HIV and other sexually transmitted diseases. The guidelines stop short of telling parents to get their sons circumcised. That is a personal decision that may involve religious or cultural preferences, said Mermin. CDC officials say that removing the foreskin, which can foster germ growth, can lower a male's risk of sexually transmitted diseases, penile cancer and even urinary tract infections. The CDC started working on the guidelines about seven years ago, when a cluster of influential studies in Africa indicated circumcision might help stop spread of the AIDS virus. "The benefits of male circumcision have become more and more clear over the last 10 years," said Dr. Aaron Tobian, a Johns Hopkins University researcher involved in one of the African studies. Circumcision has been practiced by Jews and Muslims for thousands of years, but did not become common in the U.S. until the 20th century. By one estimate, only 25 percent of U.S. male newborns were circumcised in 1900. It gradually became the cultural norm, and in the 1950s and 1960s surpassed 80 percent. But then the trend reversed. Part of it had to do with changing demographics, as the U.S. population grew to include larger numbers of Mexican-Americans and other ethnic groups that did not traditionally circumcise their children. Also, opposition to the procedure was aided by the Internet and by the neutral stance of physicians' groups. A wave of U.S. state programs stopped paying for newborn circumcisions. By 2010, the newborn circumcision rate was down to about 58 percent, according to one CDC estimate. But more medical evidence came in supporting the procedure -- particularly three rigorous and influential studies in Africa that looked at the spread of HIV and other sexually transmitted diseases in circumcised and uncircumcised men and their partners. In the new guidelines, the CDC says there is now strong evidence that male circumcision can: reduce a man's risk of getting HIV from an infected female partner by 50 to 60 percent; reduce the risk of genital herpes and certain strains of human papillomavirus by 30 percent or more, and lower the odds of urinary tract infections during infancy and cancer of the penis in adulthood. Studies have not shown that circumcision will reduce an HIV-infected man's chances of spreading the AIDS virus to women. And research has not found circumcision to be helpful in stopping spread of HIV during gay sex. The guidelines say circumcision is safer for newborns and infants than for older males, noting that the complication rate rises from 0.5 percent in newborns to 9 percent in children ages 1 to 9, according to the CDC. Minor bleeding and pain are the most common problems, experts say. For the next 45 days, the CDC will receive public comment before finalizing the guidelines next year.