A former aide to the chief fund-raiser at Washington Hospital Center was sentenced in U.S. District Court yesterday to serve one to three years in prison in connection with a scheme in which she allegedly embezzled more than $119,000 that had been set aside to administer a program for needy patients.

Margarette E. (Tina) Whited, 43, a hospital employe for 10 years, had pleaded guilty in January to one count of mail fraud. After imposing the prison term yesterday, Chief Judge John Lewis Smith Jr. said Whited must surrender to law enforcement officials and begin serving her sentence within one week.

Assistant U.S. Attorney Thomas J. Tourish Jr. alleged in court papers that from 1974 to 1981 Whited submitted 38 phony invoices, totaling $119,000, to the hospital's accounting office for work allegedly done for its Needy Sick Fund.

The prosecution asserted that Whited used the money for her personal expenses, including credit card bills, and to make mortgage payments on a home at 817 Taylor St. NE and one at Oyster Harbour in Annapolis, which she purchased for $125,000 in 1979.

Whited worked as a secretary and administrative assistant to I. Brewster Terry, the director of development for the Hospital Center. A hospital spokesman has said that the money allegedly stolen by Whited did not come from donations to the Needy Sick Fund bur rather from funds set aside to administer the program.