LOS ANGELES — In a world with few givens, there have always been a handful of life guidelines that American women could follow. Never date your best friend's ex. Always have at least one good pair of shoes. Get an annual mammogram starting at age 40.

But the mammogram advice — which women have been gleaning for years from pamphlets in doctors' offices, fashion magazines and the tags of pink kitchen appliances sold to raise cancer research money — has been turned on its head with the announcement by the U.S. Preventive Services Task Force that women without unusual cancer risks should not begin regular screening for breast cancer until age 50.

To a large degree, in interviews with women in several cities on Tuesday and comments posted on the Web, the response to the new guidelines had less to do with medicine than with a general approach to health care — and indeed life itself.

Are you the sort for whom shivering in a paper gown, enduring discomfort and waiting a week for results is so unnerving that you are thrilled for a decade-long reprieve? Or are you that woman who gets an extra breast sonogram with your gynecologist even when it is not medically indicated? Do you trust scientists or prefer your own gut?

“;Why all of a sudden this change?”; said Karen Sun, 41, who was loading her groceries into her car here in Los Angeles. “;It feels out of nowhere.”;

Sun said she planned to ignore the news and keep going for mammograms. “;I will still do it, definitely. I guess I've reached 40, the age I thought I'd start, and an age when you really start thinking about taking care of yourself.”;

Other women who have long been suspicious of the efficacy of annual checks, greeted the announcement with enthusiasm.

  Mammogram Controversy Debated In Local Medical Community

 

Now that a government panel has said women should not get a mammogram until they are 50, local experts are debating the topic.

[ Watch ]

 

“;I've been waiting for common sense regarding mammograms for years,”; said Nancy Moylan, who posted a comment on nytimes.com.

“;Sure, I know plenty of women who have breast cancer,”; said Moylan, 51, of Nantucket, Mass., in a telephone interview. “;And I know many, many women who've received false-positives. It always struck me that most women seemed so relieved to know that they don't have cancer that they never took the next step and said 'Hey, why was I just put through that anxiety? I've had all these invasive tests and worry only to find out that the mammogram isn't all it's cracked up to be?”;'

The task force also recommended that women age 50 to 74 should have mammograms every two years rather than every year and, in perhaps the most surprising advisory, that doctors should stop advising women to regularly examine their own breasts.

For those who carefully follow the advice of the scientific and medical communities about which exams and screening tests are needed annually, there can be a sort of relief when studies step in to make choices for you.

Catherine Patyk, who lives in Chicago, felt “;shocked,”; by the latest advice, but a tiny bit comforted, too. “;I just turned 40, and still haven't gone to get my first mammogram,”; Patyk said. “;This made me feel like 'Oh, I'm off the hook then.”;'

But it is also clear that vast experience with friends who have had breast cancer carried far more weight with many women than the new guidelines, which like those concerning fiber, fat, exercise and myriad other medical advisories, seem ever changing. At times it seems to some women that scientists and drug company executives know little more than your mom.

“;I already don't trust these big groups who issue statements like this, but this really makes me question,”; said Ziba Sami, 37.

“;I have little kids, 6 and 8, and I have to be here to care for them. I can't take risks,”; said Sami, of Los Angeles, adding, “;To tell women that self exams are not necessary, that is absurd. I think the FDA and insurance companies can be a bit like mafias, there are motives that we don't see.”;

Sal Kibler, 55, an executive in Atlanta who has been getting mammograms every year and performing self-checks since she was 40, had a mammogram this week. Kibler said she will continue to do so every year, as well as check her own breasts.

“;It doesn't cost that much,”; she said. “;It's not invasive. It's relatively harmless and quick and painless. It would be hard for me to just change my mind at this point. It would be different if I could see some significant harm or expense.”;

In comments posted on nytimes.com in response to an article about the new guidelines, many women said they viewed them in the context of the debate on health care, and feared that cost containment was somehow leading the scientific charge.

“;I cannot help but think that this decision has less to do with protecting a woman's health and more to do with the financial advantages gained through less insurance coverage,”; one woman posted under the handle JAG. “;While I certainly understand the risks of over-treatment, I have gotten to know — firsthand — a shocking number of young women under 40 who have been diagnosed. Very often, there are no symptoms, other than those detectable through a mammogram or a sonogram. And very often (as in my case) there is no genetic history of the disease.”;

And still there remains plain old confusion. Leslie Haltiner, a teacher's aide in Denver, said she was uneasy with the idea of shifting her own approach to breast cancer detection based on new federal guidelines without first knowing the medical specifics behind them, and also what oncologists and breast cancer awareness groups were saying.

“;Everything I've heard, from the health advertisements to the medical professionals, says that even if you don't have a family history of breast cancer, it doesn't mean you won't get it,”; Haltiner said. “;This sends a real confusing message. Wow, they're doing a complete 180.”;