Now, women in their 40s have the added anxiety of trying to figure out if they should even be getting one at all.
A government task force said Monday that most womenand should get one every two years starting at 50 - a stunning reversal and a break with the American Cancer Society's long-standing position. What's more, the panel said breast self-exams do no good, and women shouldn't be taught to do them.
The news seemed destined to leave many deeply confused about whose advice to follow.
"I've never had a scare, but isn't it better to be safe than sorry?" asked Beth Rosenthal, 41, sitting in a San Francisco cafe on Monday afternoon with her friend and their small children. "I've heard of a lot of women in their 40s, and even 30s, who've gotten breast cancer. It just doesn't seem right to wait until 50."
Her friend agreed. "I don't think I'll wait," said Leslie David-Jones, also 41, shaking her head.
For most of the past two decades, the American Cancer Society has been recommending annual mammograms beginning at 40, and it reiterated that position on Monday. "This is one screening test I recommend unequivocally, and would recommend to any woman 40 and over," the society's chief medical officer, Dr. Otis Brawley, said in a statement.
But the U.S. Preventive Services Task Force, a government panel of doctors and scientists, concluded that such early and frequent screenings often lead to false alarms and unneeded biopsies, without substantially improving women's odds of survival. Those false positives led the task force to suggest new guidelines, reports CBS News medical correspondent Dr. Jon LaPook. About 90 percent of abnormal mammogram findings are benign.
"Mammography is not as sensitive a tool in general in younger women because their breast tissue is more dense," Dr. Freya Schnabel told LaPook.
Breast cancer survivors who were diagnosed at a young age were among the more vocal critics of the new guidelines.
"This sure seems like a big step backwards to me," said Debbie Hayes, who was diagnosed with Stage 2 breast cancer at age 33 after finding a lump during a self-exam. A mammogram, ultrasound, biopsy and finally a mastectomy and chemotherapy followed.
"People are being diagnosed even in their early 20s," said Hayes, now 53 and a volunteer coordinator for the Chicago-based Breast Cancer Network of Strength. "Mammograms are a key element of that."
But another breast cancer survivor thought the new guidelines sounded about right - even though she was diagnosed at age 37, two years ago.
"They seem pretty sensible to me," said Claire Mayne, of San Francisco. "The death rate is not going down because of the earlier mammograms. I'd feel comfortable telling a friend to wait until she was 50."
Mayne was more doubtful, though, about the advice on self-exams; that's how she found her own cancer.
Most women in their 40s interviewed for this article said they planned to stick with the old mammography recommendations, at least for now.
"I have two young children," said Amber Smart, a 47-year-old mother in Agoura Hills, Calif. "There's a lot of years left that they need me." She's been having mammograms every six months, since she was 44, to make sure that certain dense areas of her breasts aren't cancer.
"I think it's kind of sad that they're basically saying, 'We can't afford to pay for the few people who may have it in their 40s, so a few people are going to die,"' Smart said.
Judy Finley, a flight attendant from Dallas, called the new recommendations "a terrible idea," and said she was especially worried that insurance companies might "pick up on this and quit paying for mammograms from 40 to 50."
"I think it would be really sad," said Finley, who was walking through the Crown Center mall in Kansas City, Mo. "And I don't know how the U.S. government or a panel of government officials can think they know better than the American Cancer Society."
But there were those who saw the new guidelines as potentially a relief, a development that could save women from endless stress, false positives and perhaps needless procedures.
"I can't tell you how many friends I have who've gone through severe worries from false scares," said Maren Waxenberg, a Manhattan mother. "At least three of them have had biopsies. And it turned out to be nothing."
Waxenberg herself, 46, has not yet had a mammogram. "I'm not concerned at this age," she said. "I plan to do it, but there's no sense of urgency."
The new guidelines are for the general population, not those at high risk of breast cancer because of family history or gene mutations.
- Most women in their 40s should not routinely get mammograms.
- Women 50 to 74 should get a mammogram every other year until they turn 75, after which the risks and benefits are unknown. (The task force's previous guidelines had no upper limit and called for exams every year or two.)
- The value of breast exams by doctors is unknown. And breast self-exams are of no value.
From a cost savings standpoint, maybe the task force could argue that the mammograms before age 50 are unnecessary, but if you're that one person who detects cancer early, "that's a big deal," CBS News medical correspondent Dr. Jennifer Ashton says.
Medical groups such as the cancer society have been backing off promoting breast self-exams in recent years. Decades ago, the practice was so heavily promoted that organizations distributed cards to be hung in the shower demonstrating the circular motion women should use to feel for lumps.
As for mammography, the panel's new recommendations are more in line with international guidelines, which call for screening to start at age 50; the World Health Organization recommends the test every two years, and Britain says every three years.
They were sharply challenged by the cancer society on Monday.
"The task force advice is based on its conclusion that screening 1,300 women in their 50s to save one life is worth it, but that screening 1,900 women in their 40s to save a life is not, Brawley wrote.
That stance "is essentially telling women that mammography at age 40 to 49 saves lives, just not enough of them," he added.
But Dr. Amy Abernethy of the Duke Comprehensive Cancer Center agreed with the task force's changes.
"Overall, I think it really took courage for them to do this," she said. "It does ask us as doctors to change what we do and how we communicate with patients. That's no small undertaking."