Education
She finished 5th in her senior national debut at the 2006 Canadian Championships.
She finished 5th in her senior national debut at the 2006 Canadian Championships.
Her highest placement at an International Skating Union Championship was 7th at the 2010 and 2012 Four Continents Championships. She also competed on the Junior Grand Prix series. She briefly tried pair skating in 2007.
She was assigned to her first Four Continents Championships where she finished 10th.
The following season, she made her Grand Prix debut, appearing at 2009 Skate Canada International and 2009 Cup of Russia. She finished 7th at the 2010 Four Continents.
She was named an alternate to the World Championships and was given her first berth to the event when Myriane Samson dropped out due to injury. Lacoste then earned a berth to her second World Championships when she placed 7th at the 2012 Four Continents, 0.18 ahead of Phaneuf.
She finished 16th at the 2012 World Championships in Nice.
Lacoste injured her right hip in autumn 2012. In early October 2013, Lacoste moved to Colorado Springs, Colorado to be coached by Christy Krall and Damon Allen. In May 2014, she announced her retirement from competition.