Born in Rouen, she was the daughter of Colette Elloy – a 1952 Olympian for France in the 80 metres hurdles. Running for the Stade Dieppe athletic club, she made her international debut as a teenager at the 1977 European Athletics Junior Championships (coming fourth) then ran at the 1978 European Athletics Championships, where she competed in the 100 metres hurdles heats only. She rose on the regional scene with a gold medal win at the 1979 Mediterranean Games, succeeding her compatriot Nadine Fricault to the title. Elloy's first national title at the came in 1979 and she went on to win five such 100 m hurdles titles in the period up to 1986.