The Belarusian has been stripped of her bronze medal at the 2008 Beijing Olympics.
"Re-analysis of Ostapchuk's samples from Beijing 2008 resulted in a positive test for the prohibited substances dehydrochlormethyltestosterone [turinabol] and tamoxifen," an IOC statement said.
Adams claimed her first Olympic gold at the event with Natallia Mikhnevich of Belarus, finishing second followed by compatriot Ostapchuk. Mikhnevich was last year stripped of her silver medal after re-testing showed a positive test for the prohibited substances methandienone and stanozolol.
Four years later Ostapchuk won gold in London, only to fail a drugs test days after competition with Adams being upgraded to the gold medal.
As it stands Adams is the only medal winner from the 2008 event and the only original medal winner from the 2012 event after London bronze medallist Yevgeniya Kolodko also failed a drug test and was stripped of her medal.
