Berthenet made sporting headlines at the 1996 World Wrestling Championships in Sofia, Bulgaria, where she picked up a silver medal in the women's 47-kg division, losing out to U.S. wrestler Tricia Saunders. On that same year, she took home her first European championship title in the same category, and continued to produce four more medals (1997, 1998, 2002, and 2003) in her career hardware. Eventually, she entered the 2003 World Wrestling Championships in New York City, New York, United States, and came strong as a top medal contender in her category. Though she finished sixth in the women's flyweight, Berthenet granted a ticket to her first Olympics and was officially selected to the French Olympic team.