Former Supreme Court Justice Sandra Day O’Connor made history decades ago when she became the first female to hold a position on the nation’s highest court.

She announced today that doctors diagnoses her “with the beginning stages of dementia, probably Alzheimer’s disease.”

She wrote: “How fortunate I feel to be an American to have been presented with the remarkable opportunities available to the citizens of our country. As a young cowgirl from the Arizona desert, I never could have imagined that one day I would become the first woman justice on the U.S. Supreme Court.”

O’Connor also wrote that she hopes she has “inspired young people about civic engagement and helped pave the pathway for women who may have faced obstacles pursuing their careers.”

Chief Justice John Roberts released this statement: