A mammogram is a common procedure that is important for women age 40 and older to have annually, according to The Austin Diagnostic Clinic. Oct. 17 is National Mammography Day, and to prepare women for what to expect, several questions and answers about the procedure follow.

What is a mammogram?

A mammogram is basically an X-ray used to examine breast tissue with a low dose of radiation. It helps doctors find tumors and other abnormalities.

With mammography, a doctor can detect breast cancer one to three years before a woman would be able to detect a lump in her breast.

"It's recommended that women over 40 get a screening annually, and possibly earlier if you are at high risk for breast cancer," said Dr. Deborah O'Connell a radiologist with The Austin Diagnostic Clinic. "Mammography, along with a monthly breast self-exam, is key in early detection of breast cancer, the second-leading cause of cancer death among women in the U.S."

How does one prepare for a mammogram?

Schedule a time when breasts are least likely to be tender," said O'Connell. "Often that can be during the week after a period. They're most likely to be tender during the week of and the week before a period is due. If you're concerned about anxiety, schedule the mammogram early in the day to avoid building up tension."

The day of the test, it's important not to use deodorants, antiperspirants, powders, lotions or any other products under the arms or on the breasts.

Metallic particles in deodorants or powders can show up on the mammogram, said O'Connell. "It's best just to forgo any product at all for the day of the exam."

What can one expect?

A patient will be asked to remove jewelry and clothing from the waist up and will be given a gown at the doctor's office or radiology lab. Plan on wearing a two-piece outfit that day to make things easier. During the procedure, the woman will stand in front of the machine and the technician places one of the woman's breasts on the film platform.

The technician will raise or lower the platform to match the patient's height, and will help the patient position her head and arms so as not to block the X-ray.

The breast is then pressed onto the platform by a plastic plate. Pressure is applied to spread out the breast tissue so that the machine gets the clearest view.

The patient will be asked to stand still and hold her breath for a few seconds. Two views of each breast are taken, one from the side and the other from the top.

How long will it take?

After the images are taken of both breasts, the technician will ask the patient to wait to make sure the images are of good quality. If they aren't the technician may ask to repeat parts of the test. The actual procedure takes about 10 minutes.

What if the patient has implants?

Breast implants can actually impede accurate mammogram readings. Make sure to tell the technician about the implants.

Experienced technologists know how to carefully compress the breasts to improve the view and avoid problems with the implant, said O'Connell.

"Women with implants should make sure, when making an appointment for a mammogram, that the technologist is experienced in performing the exam on women with implants.

How will the results be made available, and who looks at them?

A radiologist -- a doctor who is trained to interpret X-rays -- will analyze the results and send a report to the patient's primary care doctor, who will then notify the patient of the results. Findings can include calcium deposits, masses or lumps, distorted tissues or dense areas in the breast.

"If there's anything in your results that are areas of concern, further testing may be necessary, including an ultrasound or a biopsy," said O'Connell.

About 10 percent of mammograms lead to more testing. "Mammography isn't fool-proof, and certain factors can create falsenegative or false-positive results."

Most abnormal findings aren't cancer, said the physician. "Because a mammogram itself isn't always enough to determine the existence of a tumor or disease, it's a good idea to follow up on any further recommended testing."

Are there other ways to screen for breast cancer?

Mammograms are currently the most common way to screen for breast cancer, but there are other technologies in the works that may improve detection.

The American Cancer Society has added an annual MRI to its list of screening recommendations for women with high breast cancer risk. Many facilities have switched to digital mammography, which allows doctors to read and store the film on a computer. Computeraided detection also is in use at some facilities today.