Born February 15, 1954 in Holyoke, Massachusetts. Donoghue has resided in Lowell with her husband John J. O'Connor since 1988.  She obtained her Bachelor of Arts degree from the University of Massachusetts in 1976 and went on to receive her Juris Doctor at Suffolk Law School in Boston, Massachusetts.  Donoghue has been in private practice since 1979 and in 1991, opened her own practice in the City of Lowell. She speaks fluent Spanish.

Donoghue  has been on the Lowell City Council since 1996 and on January 5, 1998, she became the second woman ever elected Mayor of the City of Lowell, Massachusetts since its inception in  1823. 

She has served on numerous subcommittees including Finance, Economic Development, Public Safety, and the Neighborhoods and University Relations. 

On a statewide level, Donoghue served as Chairperson of the Transition Team for Governor Paul Cellucci and Lieutenant Governor Jane Swift.

Donoghue is a member of the Massachusetts Bar Association, the Greater Lowell Bar Association, and the Criminal Justice Act Board – United States District Court, District of Massachusetts.

Donoghue also serves on the Board of Directors of several area organizations, including: The Whistler House Museum of Art, Girls Incorporated of Greater Lowell, Saints Memorial Medical Center, and Merrimack River Valley House.