Early in her career, Jepkemoi competed in a variety of events; her main event was the 5,000 metres, in which she placed fifth at the 2011 Kenyan Championships.[2][3] At the 2011 All-Africa Games in Maputo she competed in both the 5,000 metres and an event completely new to her, the 3,000 metres steeplechase;[2] she placed fourth in her main event but won an unexpected gold in the steeplechase, running 10:00.50 and outkicking Ethiopia's Hiwot Ayalew to win Kenya's first athletics gold medal at the Games.[2][3]
In 2012 Jepkemoi started concentrating on the steeplechase and her times improved; her best time that year was 9:23.53, which she ran at the Gugl Games in Linz.[3] She scored her first IAAF Diamond Race points with a third place at Weltklasse Zürich after Sofia Assefa, the original winner, was disqualified for a lane violation.[4][5] At the Kenyan Championships, Jepkemoi placed second and gained selection for the African Championships in Porto Novo, where she won bronze despite falling at the water jump.[6][7] At the Kenyan Olympic Trials, however, she only placed fifth and failed to qualify for the Olympic team.[8]Track & Field News ranked Jepkemoi ninth in the world for 2012, her first top ten ranking.[9]
In 2013, Jepkemoi only placed fourth at the Kenyan Championships but third at the World Championships Trials, qualifying for the Kenyan team to the 2013 World Championships in Athletics in Moscow.[3][10] At the World Championships, she placed sixth with a new personal best time of 9:22.05;[3] she ended the year ranked seventh in the world, up two places from the previous year.[9] In 2014, Jepkemoi's best race was at the Ostrava Golden Spike meeting, where she ran 9:22.58 and narrowly won ahead of Morocco's Salima Alami.[3][11]
Jepkemoi opened 2015 with a near-personal-best of 9:22.11 at the Doha Diamond League meeting, placing third behind Ethiopian runners Virginia Nyambura and Ayalew.[12] In her next Diamond League meeting, the Golden Gala in Rome, she improved her personal best by almost seven seconds and won in a meeting record 9:15.08, defeating both Nyambura and Ayalew.[13] Three days later she was runner-up to Nyambura at the British Grand Prix in Birmingham, her third consecutive Diamond Race points finish.[3]
