Olympic marathon champion Jemima Sumgong has been banned for four years for EPO.
A doping tribunal rejected her explanation that the blood-boosting hormone was in her system because she had been treated at a hospital in Kenya days before her failed test.
The tribunal found no legitimate record of the hospital visit and treatment for an ectopic pregnancy claimed by Sumgong, it said on Tuesday in a decision released by the Anti-Doping Agency of Kenya.
The panel ruling on her case said the 32-year-old Sumgong's hospital story was "inconsistent at best".
"We might go so far as to state that the athlete's attempt to explain how the substance entered her body bordered on an attempt to deceive the panel," the ruling said.
Sumgong became the first Kenyan woman to win Olympic gold in the marathon when she triumphed at last year's Rio de Janeiro Games. She failed an out-of-competition test on February 28 and was banned for four years from April 3, the date her provisional suspension was announced.
It makes her ineligible for the 2019 world championships and the 2020 Tokyo Olympics.
Sumgong is the highest-profile athlete on a long list of Kenyans to be banned for doping in recent years.
Sumgong waived her right to have her backup "B" sample tested and said she had taken EPO unintentionally after visiting Kenyatta National Hospital in Nairobi six days before her doping test to be treated for an ectopic pregnancy.
The Olympic champion couldn't provide the name of the doctor who supposedly treated her or reliable documents showing she was admitted to the hospital, the tribunal said. It said documents she provided were denounced as fake by the hospital.
The hospital visit was not disclosed by Sumgong at the time of the doping test.
The only record the hospital had of a visit by Sumgong was in April, when she inquired about treatment for ectopic pregnancies.
The Anti-Doping Agency of Kenya said it believed Sumgong was taking EPO ahead of the defence of her London Marathon title in April.
Sumgong has also won the Rotterdam and Las Vegas Marathons and finished runner-up in the Boston, Chicago and New York races.
