Born in Vinnytsia, Krevsun grew up around the track as her family was heavily involved in sports; her mother Militina Moskvina was an 800 m runner while her father, Yuriy Hurtovenko, was a talented shooter.

The family lived in poverty, affecting her athletics career, but she was invited to attend the Donetsk Sport College in 1998 and met Serhiy Krevsun, an amateur boxer, whom she would later marry.

A loss to Nataliya Tobias at the 2006 national championships inspired her to restart her professional career and she began training with Iryna Lishchynska.

[6] After strong performances in the 800 m at the 2008 IAAF Golden League meets, including beating World Champion Janeth Jepkosgei, she gained self-confidence and focused on competing at the 2008 Summer Olympics.

[4] She started the 2009 season well with a win at the inaugural European Team Championships, setting a world-leading time of 1:58.62 and fending off fast performances from Yekaterina Kostetskaya, Élodie Guégan and Hannah England.

[7] She competed for Ukraine at the 2009 World Championships, finishing fourth in the 800 metres final,[8] although winner Caster Semenya was asked to take a gender test.