THURSDAY, Sept. 24, 2026 (HealthDay News) -- Dense breast notification and insurance coverage laws are associated with increased use of supplemental ultrasonography among women undergoing mammography, according to a study published online July 29 in JAMA Network Open.Dong-Won Kang, Ph.D., from Ajou University in Suwon, South Korea, and colleagues conducted a retrospective, quasi-experimental cohort study to examine the differential association of dense breast notification and insurance coverage laws with supplemental imaging use. Overall, 12.6 million women (age 40 to 64 years old) undergoing screening mammography with continuous insurance enrollment for at least six months after index mammography were followed for up to six months.Of 12,555,082 women undergoing mammography, 9.0 and 0.6 percent received supplemental ultrasonography and supplemental magnetic resonance imaging (MRI). The researchers found higher use of ultrasonography and MRI in association with notification mandates (odds ratios, 1.09 and 1.09). Higher odds of supplemental ultrasonography use were seen in association with insurance coverage (odds ratio, 1.88). Including information on supplemental screening and targeting notification only to women with dense breasts were both associated with higher odds of ultrasonography use among states with notification mandates (odds ratios, 2.84 and 1.32, respectively)."Not everyone with dense breasts needs supplemental screening, but you first need to be aware whether or not you have dense breasts to make that decision in consultation with your health care provider," senior author Chan Shen, Ph.D., from Penn State College of Medicine in Hershey, said in a statement.Abstract/Full Text.Sign up for our weekly HealthDay newsletter