Berg was born in Whittier, California and raised in nearby Santa Fe Springs, graduating from Santa Fe High School in 1993. Berg and her twin sister enrolled at Fresno State and started for the school's softball team. In her first season, she was named a National Fastpitch Coaches Association Third Team All-American. The Bulldogs made it to the WCWS and took their first game before dropping back-to-back shutout games against eventual champions the Arizona Wildcats and the Oklahoma State Cowgirls on May 27, 1994. Berg had two hits in the tournament.