WASHINGTON -- Women can delay their first Pap test for cervical cancer until they turn 21, and many can wait longer to go back for follow-up screenings, according to new guidelines released today by a major medical group.

The American College of Obstetrics and Gynecologists recommended the change after concluding more frequent testing did not catch significantly more cancers and resulted in girls and women having unnecessary stress, anxiety and sometimes-harmful treatments because of suspicious growths that would not cause problems.

"We really felt that the downsides of more frequent screening outweighed any benefits," said Dr. Alan Waxman, a University of New Mexico obstetrics and gynecology professor who led the guidelines revision. "More testing is not always more intelligent testing."

The change comes amid controversy over new recommendations from a federal task force that women wait until age 50 before they begin having routine mammograms, and that women age 50 to 74 scale back to getting the breast exams routinely only every two years.

Officials said the release of two sets of guidelines the same week was coincidental.

The Obama administration distanced itself from the breast exam guidelines announced Monday by a federal task force, saying the panel does not set government policy or determine what services are covered by the government.

"There's something about health reform and guidelines that makes people think they're telling women to do less screening to save money," said Cindy Pearson of the Washington-based National Women's Health Network advocacy group. "But we don't have any concerns that women are being asked to give up something that is helpful. These recommendations are sound," she said, referring to cervical cancer screening.

Several experts said a backlash against those guidelines could be less likely because of a variety of factors: They said there is greater scientific accord about the risks and benefits of cervical cancer testing than mammography; the recommended revisions are less dramatic; and the guidelines were issued by a private medical group, not a government-appointed task force.

"I can certainly understand why people are concerned about linking these -- it's clear we're going to have to carve billions [of dollars] out of the health care system," said Dr. Thomas Herzog, chairman of gynecologic oncology at Columbia University New York Presbyterian Hospital.

The American Cancer Society, which has led opposition to the revised mammography guidelines, was involved in discussions leading up to the Pap test guidelines and will consider them in reevaluating its own recommendations, an official said. "We are persuaded that the guidelines are really consistent with the evidence," said Robert Smith, the society's director of cancer screening.

The National Cervical Cancer Coalition, a patient advocacy group, endorsed the recommendations.

Washington correspondent Daniel Malloy writes the "Pittsburgh On The Potomac" blog exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.