Sumgong’s ban was announced today by the Anti-Doping Agency of Kenya (Adak), which ruled Sumgong ineligible from April 3.

The gold medalist at Rio 2016 failed a test on February 28 and declined to have her backup B sample tested.

Sumgong told a tribunal that she had tested positive for the banned blood booster Erythropoietin (EPO) after being given a blood transfusion at the Kenyatta National Hospital on February 23 for an ectopic pregnancy. 

She said she had also received other unknown medications by an unidentified doctor.

Sumgong stated that it was unfortunate offence and unintended.

She had indicated that she had not disclosed this information to her husband Noah Talam, who is also her coach, because it was a taboo condition.

The anti-doping agency rejected this explanation after Sumgong failed to provide documents relating to her hospital visit.

Last year, Sumgong became the first Kenyan female to win Olympic gold in the marathon.

The International Association of Athletics Federations (IAAF) announced on April 7 this year that the 32-year-old had tested positive for EPO.

Adak handed the 2015 London Marathon champion the mandatory four-year ban.

According to a ruling by the Tribunal, signed by chairman John Ohaga, Sumgong broke Article 10.2.1 and 10.11.2 of the Anti-Doping Rules (ADR) and Wada Code.

Sumgong has the right to appeal, provided under Article 13.2.1 of the Wada Code and Rule 42 of the IAAF Competition Rules and Article 13 of ADR.

Last month, Adak banned five Kenyan runners, Shieys Chepkosgei, Florence Chepsoi, Joseph Kariuki Gitau, Sharon Ndinda Muli and Ken Kirui for doping offences.

In May it was reported that three training partners of Sumgong had been suspended from competitions "until investigations into doping allegations are completed".

The trio included Paris Marathon champion Purity Rionoripo and Sarah Chepchirchir, winners of this year's Paris and Tokyo Marathon races.

The third was Visiline Jepkesho, last year's Paris Marathon champion.