Donahue was born in Saskatchewan, Canada, of Irish ancestry. As a young girl she learned to play baseball with the help of her brother in their family farm, and later played softball at school and in Moose Jaw for the local Royals team. In 1945 Donahue was invited by an All-American Girls Professional Baseball League scout to spring training the next year in Pascagoula, Mississippi. She agreed to try out and was assigned to the Redwings, an expansion team based in Peoria, Illinois.[2] During her four seasons in the league, Donahue was primarily a catcher, but played every position except first base and pitcher. She hit .127 in 287 games, and committed 56 errors in 1051 chances for a .947 fielding average.[3]
In 2020, Netflix released a documentary, A Secret Love, which chronicles Donahue's ultimately 72-year relationship with her wife Emma Marie "Pat" Henschel. The couple got married on Donahue's birthday in 2015.[8]
The character of Jess McCready from the 2022 reboot series A League of Their Own of the 1992 movie of the same name is partially based on Donahue.