PETERINA - EFFME is quite right but there are two important considerations behind the age for scans.
The first unfortunately is insurance. Many insurance companys will not pay for a mammography before 40. Some legislation was under way to require mamogrophy for special at-risk populations (such as Jewish Women in Long Island). I don't know if that was ever passed.
Virtually all doctors would like woman to get a baseline reading around 30 or even earlier. The idea with the baseline mamogram is that it almost definitely won't pick up tumors, but it will show a picture of all healthy breast tissue and can often clarify a later scan that might look suspicious. (The earlier scan can show it was a cyst for example and not a problem). Most women don't get these baselines b/c insurance companies won't cover them.
The second crucial factor is special risk groups. My mom had breast cancer and a resulting radical mascectomy. My daughters (and son) are at increased risk, compunded by the abnormally high incidence of breast cancer on long island.
For those in the "at risk" catagory, earlier scans are often recomended.
And Lisa, don't worry. I've been told that it's not nearly as painful as birth.
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