Niewiedział had planned to retire after the London Paralympics, but the experience of competing in front of a cheering capacity crowd that the 2012 Games provided changed her decision. Further success followed at the 2013 IPC Athletics World Championships in Lyon where she took gold in her favoured 1,500m. She furthered this success two years later at the World Championships in Doha, taking three gold medals in the 400m, 800m and the 1,500m races.