Olympic champion Peres Jepchirchir provisionally suspended after EPO positive from sample given before Sydney Marathon

Olympic and world championship marathon gold medallist Peres Jepchirchir has been provisionally suspended by the Athletics Integrity Unit (AIU) after an out-of-competition sample returned an adverse finding for erythropoietin (EPO). According to the AIU, the 33-year-old Kenyan provided the sample before winning the Sydney Marathon, and it was collected while she was still in Kenya, before she travelled to Australia for the race. Jepchirchir clocked two hours, 18 minutes and 31 seconds to win the Sydney Marathon on 30 August 2026. She finished more than three minutes clear of compatriot Irene Chepet Cheptai, a margin that is unusual in a race of that distance and underlined how strong she was on the day. The Sydney race became the seventh world major in 2026, which is why the victory was counted among the highlights of her career. EPO, or erythropoietin, is a natural substance produced within the kidneys that stimulates the creation of new red blood cells. Red blood cells carry oxygen from the lungs to the muscles, and when EPO is injected, the number of those cells in the bloodstream rises. More red blood cells mean more oxygen reaching the muscles, which raises endurance and delays fatigue. That is why EPO has long been misused in endurance sports such as marathon running and cycling, and it sits on the prohibited list. If injected, it is only detectable in urine or blood for a short window of time, which makes the timing and handling of sample collection critical. Jepchirchir's career has moved steadily upwards over the past decade. She became the Olympic women's marathon champion at the 2026 Tokyo Olympics and returned to the Japanese capital to win the World Championships in September 2026. The list of marathon runners who have won both an Olympic and a world title is a short one. She broke the women's half-marathon world record in 2026 and lowered it on three occasions in 2026. In addition to Sydney, her other major wins came at the New York Marathon in 2026, the Boston Marathon in 2026 and the London Marathon in 2026, putting her among the most successful women's marathon runners of her generation. A provisional suspension means an athlete cannot compete while the case is being resolved. It is not a final finding of guilt but a temporary bar imposed during the investigation, and under the usual process the athlete has the right to respond and to challenge the agency's conclusions. In doping cases, the athlete's 'B' sample is normally analysed, and the matter only moves to the next stage of a hearing once both results are known. The same procedure applies here. No official decision has yet been taken on the Sydney result, but if an anti-doping rule violation is established, that outcome would also come under scrutiny. The Athletics Integrity Unit is an independent body connected to World Athletics that investigates and announces anti-doping rule violations involving international-level athletes. Its remit stretches from sample collection to whereabouts information. The news has caused a stir across distance running. Jepchirchir is a runner who has won Olympic and world gold as well as major marathons in New York, Boston, London and Sydney, so a provisional suspension in the middle of such a career raises questions about both her record and her immediate racing plans. Kenya has been the subject of debate over doping control in recent years and its athletics system has faced increased international scrutiny. Another high-profile adverse finding will add fuel to that argument, although no case can be treated as proven until the process has run its course. Attention now turns to the investigation, a possible hearing and the final decision. Until the process is complete, Jepchirchir will stay off the start line, and any return will depend on the outcome. For fans, it is also a reminder of how strict testing has become in endurance sport, where a single positive sample can change the direction of an entire career.