[3] In 2015, she was banned from competing for three years by the Court of Arbitration for Sport for irregularities in her biological passport[4][5] and stripped of her status as a Spanish national athlete.

Her personal best in the steeplechase is now listed by the IAAF as 9:09.39 from the last race she ran six days before the official doping ban period went into place.

Domínguez beat her own 3,000 metre steeplechase national record by over five seconds at a track meet in Málaga in June 2009.

She and Yuliya Zarudneva engaged in a duel for the title, but it was the Russian who prevailed, reversing their positions at the World Championships the previous year.

"[10] Domínguez fell pregnant that year and ruled herself out of the 2011 season in order to focus on starting a family with her husband Diego Bercianos.

[12] In December 2010, Domínguez, together with 13 other people including her coach, were arrested during "Operación Galgo" (Operation Greyhound), a major criminal investigation into sports doping carried out by the Guardia Civil.

[13] The lack of prosecutions arising from Operación Puerto led to criticism of the Spanish authorities for an apparently ineffective approach to doping in sport, and prompted the Spanish government to pass tougher anti-doping legislation that now makes the supply and use of performance-enhancing drugs illegal, with penalties including jail terms.

A blood bag seized during the Puerto investigation, and which Eufemiano Fuentes had recorded as belonging to an athlete whom he codenamed "Rosa", accompanied by her mobile telephone number, was attributed to Marta Domínguez.

In one conversation presented at the trial Domínguez, according to Garcia, asked him for how long EPO is detectable in blood tests after use.

[16] However, the judge ruled that the wiretapping of Domínguez phone was not justified, and ordered to exclude this and all other conversations from evidence of the trial.

[19] On 19 November 2015, she was banned for three years by the Court of Arbitration for Sport and was stripped of her 2009 gold medal from the IAAF World Championships in Berlin.