Russia's Olympic and double world hammer throw champion Tatyana Beloborodova has been provisionally suspended for doping, the IAAF said.
Beloborodova, who previously competed under her maiden name Lysenko, won world titles in 2011 and 2013 and Olympic gold at London 2012.
"The IAAF can confirm that Tatyana Beloborodova (Lysenko) is provisionally suspended. As with all ongoing cases the IAAF will not comment further until its conclusion," world athletics' governing body told Reuters.
Russian state media reported on Monday that a sample Beloborodova gave at the 2005 world championships, where she took the silver medal behind Yipsi Moreno of Cuba, was positive after a retest.
The 32-year-old was suspended from 2007 to 2009 for using steroids and a second positive test could lead to a longer ban.
The former world record holder returned to competition last year after having a baby.