Coburn competed in the 2011 World Championships (12th) and qualified for the 2012 London Olympic Games in the 3000-meters steeplechase (8th). Coburn launched her professional career in 2013 by signing with New Balance. In 2014, she secured her first Diamond League victory at the Shanghai Diamond League and broke the American record in the 3000-meters steeplechase with 9:11.42, also winning the IAAF Continental Cup in Marrakesh. She won the USATF Championships to qualify for the 2015 World Championships in Athletics (5th).
In 2016, Coburn set another American record in the 3000-meters steeplechase at the Prefontaine Classic and made history at the Rio Olympics by winning a bronze medal, becoming the first American woman to medal in an Olympic steeplechase event. Her trajectory of success continued into 2017, setting a world-best time in the Distance Medley Relay (DMR) at the New Balance Indoor Grand Prix. Later that year, Coburn achieved gold at the World Championships in London, setting a championship record of 9:02.58 and becoming the first American woman since 1952 to win a world steeplechase title. Awarded the prestigious Jackie Joyner-Kersee Award by USATF in 2017, Coburn followed this with a silver medal at the 2019 World Championships in Doha (9:02.35 personal best), and qualified for her third Olympic Games in 2021 by winning the US Olympic Trials for the 3000-meters steeplechase.
Throughout her distinguished career, Coburn has earned 10 US National Championship titles, alongside multiple appearances at the Olympic Games (2012, 2016, 2020) and five World Athletics Championships, placing 8th in her most recent appearance in 2022. While a 2024 injury prevented her from competing in the Olympic Trials for her fourth Olympic appearance, Coburn’s commitment extends beyond the track. She founded the annual Elk Run 5k, a fundraising event supporting the Crested Butte Cancer Support Community.