Her principal race of 1991 came over 10,000 m at the 1991 World Championships in Athletics. Although she qualified easily with a run 31:55.97 minutes, she could not match this form in the final, in which she finished 19th and was over a minute slower. Sergent's career began to decline and in 1992 she came 27th at the 1992 World Cross Country race and failed to make it out of the 10,000 m heats at the 1992 Barcelona Olympics. She was part of the bronze medal-winning women's team at the 1993 IAAF World Cross Country Championships, but it was Farida Fatès who led the team while Sergent finished in 34th place. At the 1993 World Championships in Athletics she was eliminated in the heats of the 3000 m in her third and final appearance at the competition. She did not end the season empty handed, however, as at the 1993 Mediterranean Games, held on home turf in Languedoc-Roussillon, she took the silver medal over 3000 m.