context: Screening mammograms save lives. They're one of the most common methods to check for breast cancer. They can find the disease before you get symptoms. If a doctor sees something questionable on your screening mammogram, it's natural you'll worry. Many suspicious areas found in these tests aren't breast cancer, but your doctor will need to take a closer look at them to be safe. So you might need another imaging test or a biopsy. A technician will position your breast between two plates. She'll then flatten and compress it to get a better image. Each breast is X-rayed in two different positions: from top to bottom and side to side. It can be uncomfortable, but the entire process takes about 20 minutes. Then the images get checked for possible signs of cancer. The American Cancer Society recommends women ages 40 to 44 should have a choice to start yearly screening mammograms if they would like. Women ages 45 to 54 should have a mammogram each year, and those 55 years and over should continue getting mammograms every one to two years. But not all groups agree. The U. S. Preventive Services Task Force recommends screening every 2 years from ages 50 through 74. They also recommend the decision to start yearly screening mammograms before age 50 should be an individual one. If your doctor tells you you're at high risk for breast cancer, or you have close family members who got the disease at an early age, you might want to consider getting screened earlier. When to start having mammograms is a decision between you and your doctor. Most experts recommend you continue to have these screenings as long as you are in good health and are expected to live at least another 10 years. Doctors spot questionable areas in up to 8% of women who have screening mammograms. If this happens to you, you may need more tests. Of those women asked to return for further testing, only 10% will have breast cancer. It can be a follow-up test after a screening mammogram that spotted something unusual. Or your doctor might recommend this test without a screening mammogram first if you have symptoms she'd like to check into further. Some women only need more mammogram images. Other women may need an ultrasound, or a biopsy. A lump or mass with a smooth, well-defined border usually isn't cancerous. An ultrasound can look inside the lump. If it's filled with fluid, it's called a cyst, and it's usually not cancer, but your doctor might recommend a biopsy. A lump that has an irregular border or a star-burst appearance raises more concern. A biopsy is usually recommended. Deposits of calcium (calcifications) can be large or small, and they might or might not be cancerous. If the deposits are very small, you may need more tests and a biopsy. These imaging tests help doctors diagnose about 75% to 85% of breast cancers. They can spot potential problems before they're large enough to be felt. Detection rates improve as a woman ages, because breasts become less dense with age. This makes tissue easier to see through on mammograms. Advancing technology raises detection rates. Three-dimensional mammography isn't available yet at all mammogram facilities. But one study showed that using 3- D mammography along with digital mammograms improved detection rates and lowered the number of women who had to return for more tests because of a suspicious finding.