After getting annual mammograms for 10 years, most women in the United States have had at least one false positive and seven to nine percent have been asked to get a biopsy, a US study released Monday found.

"We conducted this study to help women know what to expect when they get regular screening mammograms over the course of many years," explained Rebecca Hubbard, a Group Health Research Institute researcher in Seattle and an author of the research appearing in the October 17 edition of "Annals of Internal Medicine."