There's more data coming out all the time and the bottom line is that getting regular mammograms after age 50 will not protect you and might even do you harm. If you have a lump you want to check out, try thermography instead. Nice update here from Mercola:
http://articles.mercola.com/sites/articles/archive/2008/11/26/why-mammography-is-not-an-effective-breast-cancer-screen.aspx