How often should be taken a mammography scan?

once a year or per doctor request

They should be every year.

Once a year unless cancer runs in your family then I think it is every three months but I am not sure. I haven't turned 40 so I have never had a mammogram.

Probably never! Check the studies, they don't seem to help, statistically speaking.

Once a year above the age of 40. But it depends on the country, since where I come from (Singapore) it's once a year for age 40-49, but once every 2 years above 50. =)

once a year after 40, unless you are at a high risl for cancer. talk to your doctor, make him aware of any family history of cancer.

first search in yahoo for anti cancer foods and start eating them. After that if you are above 40yrs go for mamogram ( which detects cancer onset before 2 years) every year if there is a history of cancer in your family otherwise go alternate year thats all. You should know the most important thing that is if cancer is detected in the primary stage then you have 100% normal life by the treatment if it is delayed the time is reduced. before taking the scan you can personally examine your breasts and if you find any abnormal lumps which are painless then immediately go for a mamography scan however one concilation is if you have given birth to two or more children then breast cancer occuring is very rare.

you should start at the age of 40 unless otherwise told to by your doctor. Then it should be repeated once a year unless you have a history of breast cancer in your family. Then it should be done every 6 months at least.

everyone's right - once a year is correct. Whoever said 3 months if there's a family history is wrong. However, if you're under the age of 40, or have dense boobs, ask for an ultra sound scan, it's totally painless and shows up all massess. When I actually had cancer the mamo picked up nothing but the ultra sound instantly showed a lump.
Hope that helps.