LePeilbet attended Arizona State University, where she majored in Sociology and graduated with Magna Cum Laude honors. Amy played for the Arizona State Sun Devils women's soccer team from 2000 to 2003. LePeilbet started all games in her career at Arizona State, playing in 74 career games. She was a three-time First-Team All-Pac-10 selection (2001–2003), two-time All-American and two-time Academic All-American.
As a Freshman, LePeilbet scored one goal (an unassisted goal against Eastern Michigan) and had one assist.
During her sophomore year, LePeilbet was considered the team's top defender. She posted one assist against Mississippi. She was named Verizon Academic All-American, was a Maroon and Gold Scholar-Athlete, and was named to the Traditional Bank All-Tournament team.
In 2002, during LePeilbet's junior year, she was considered one of the main reasons the team tied the school record with five straight shutouts. She received an honorable mention All-American by Soccer Buzz, earned NSCAA second-team All-West Region acclaim and was named to the Soccer Buzz second-team All-West Region. LePeilbet was given All-Pac-10 First Team honors for the second straight year. She was first-team Pac-10 All-Academic, Academic All-American and all-region selection. She scored two goals and had one assist on a game-winning goal against Northern Arizona.
During her senior year, LePeilbet was a main component in helping to carry the Sun Devils into the second round of the NCAA Championships, the team's second consecutive and third NCAA appearance in the last four years. She helped the team finish with a 13–5–3 record and a final national ranking of 14th in the nation. As Arizona's top defender, LePeilbet also scored three goals, including two game-winners while leading a defense that allowed 1.05 goals per game and posted eight shutouts.
LePeilbet was a member of the United States U-21 national team from 2002 to 2003, and played a critical role in the defensive backfield for the team that won the Nordic Cup in both 2002 and 2003. She made her first appearance for the full United States national team in 2004 against Sweden. LePeilbet was unable to participate in the 2007 World Cup and 2008 Summer Olympics in Beijing due to her recovery from an ACL injury.
In 2011, LePeilbet competed in the 2011 FIFA Women’s World Cup held in Germany, where the USA team finished second behind Japan. She played 535 minutes in all six matches the USA team played in Germany. She was substituted in two group matches against Columbia and Sweden.
LePeilbet’s match record at the 2011 FIFA Women’s World Cup included three wins against Korea DPR and Columbia in group stage, and France in the semifinal; one loss against Sweden in the group stage; and two draws with Brazil in the quarter-final and Japan in the final.
In May 2012, LePeilbet was one of 18 players to be named to the roster for the 2012 Summer Olympics in London. At the Games, she competed in five of the six matches that her team USA played. She accumulated 436 minutes of playing time. Her match record at the 2012 Summer Olympics was five wins, no losses and no draws.
1998–2002: LePeilbet was a member of the Chicago Cobras of the W-League. She was one of only three high school students to be named to the team's roster.
2005: LePeilbet appeared in eight games (696 minutes) and scored one goal for the Arizona Heatwave. The Heatwave came in second in the Western Conference with a 10–3–1 record during the season.
2006-2007: Recovering from an ACL injury.
2008: She played for the Pali Blues in the Pacific Palisades area of Los Angeles, California. She appeared in 12 games (1,080 minutes), scored two goals and provided one assist…The Blues came in first in the Western Conference with a 12–0–0 record and clinched the W-League championship title with a 2–1 win over FC Indiana. During the final, LePeilbet scored the equalizing goal with a header off of a corner kick in the 83rd minute. As a result, she was named the Most Valuable Player of the W-League Championship. She was also named to the W-League Championship All-Tournament Team.
2009-11: With the arrival of Women’s Professional Soccer, LePeilbet was drafted by the Boston Breakers fourth overall in the 2008 WPS General Draft. In the 2009 inaugural season, she appeared in 19 games (1710 minutes), all of which were starts. Following a strong season, LePeilbet was selected the 2009 WPS Defender of the Year. During the 2010 season, LePeilbet played every minute of 22 games for the Boston Breakers as the center of the defense and was named for the second time running the WPS Defender of the Year (the only WPS player to win the award two years back-to-back) and to the WPS All-Star Game. In 2011, she played in 10 matches for the Breakers, but spent most of the season with the United States national women’s soccer team training for and playing in the 2011 FIFA Women’s World Cup.
2013: Amy was a member of the Chicago Red Stars but did not play while she recovered from her second ACL injury.
2014-15: FC Kansas City traded for LePeilbet prior to the 2014 season. She spent the first half of the season finishing rehabilitation from ACL surgery. In 2015, she played every minute of the regular season for Kansas City scoring two goals and was voted a finalist for the league Defender of the Year Award, as well as being named to the Best XI. FC Kansas City would go on to win the NWSL Championship in both 2014 and 2015.