If you're a low-income woman, you're more likely to get screened for breast cancer if you live in a state that expanded Medicaid under the Affordable Care Act than in a state that didn't.

According to new research, low-income women who lived in a handful of early-adopter states that implemented Medicaid expansion by 2011 were 25 percent more likely to be screened for breast cancer in 2012 than women in non-expansion states. That's a big change from 2008, when low-income women in both sets of states had similar odds of being screened. The study was presented Monday at the annual meeting of the Radiological Society of North America.

The researchers had hoped to see an effect from the Medicaid expansion, says lead author Soudabeh Fazeli Dehkordy. "We would expect to see actually greater differences if we redo the analysis today with 2015 [data]," says Fazeli Dehkordy, a resident at St. John Providence Hospital in Southfield, Mich.

Under the Affordable Care Act, states had the option of expanding Medicaid to cover low-income people living at or below 138 percent of the federal poverty level. Thirty states and the District of Columbia have expanded the health insurance program for low-income people, while 20 states are not adopting the expansion at this time.

Fazeli Dehkordy and her colleagues used data from the 2008 and 2012 Behavioral Risk Factor Surveillance System to look at roughly 31,000 American women ages 40 to 70 who self-reported how often they got mammograms. When the researchers adjusted for age, race, education and income, they found that low-income women in the early-expansion states in 2012 – which included California, Connecticut, Minnesota, New Jersey, Washington and the District of Columbia – were 25 percent more likely to get screened than women in non-expansion states.

Several studies have indicated a general decline in mammography rates following updated recommendations from the U.S. Preventive Services Task Force in 2009, Fazeli Dehkordy says. Those recommendations suggested that women could wait until age 50 before beginning regular mammograms and, at that point, begin getting them every other year. "There has been a lot of controversy regarding the importance of screening mammography, especially regarding the best age," Fazeli Dehkordy says.

Indeed, the guidelines can still be confusing to women: the American Cancer Society updated its guidelines in October, pushing back the age at which it recommends women begin annual screenings from 40 to 45.

Yet despite the overall decline in screening rates, screening rates among low-income women stayed steady from 2008 to 2012 in states that expanded Medicaid early on, the researchers found.

Copyright 2016 Kaiser Health News. To see more, visit Kaiser Health News.