However, there's controversy whether all 16 of them are convicted in a death penalty, as some reports say one of them was imprisoned for life.
On Thursday, the Iraqi authorities handed over four women and 27 children from IS families to Russian Federation, after being cleared of charges of involvement in terrorist operations against civilians or security forces, Iraqi Foreign Ministry said.
All 15 said they had married Isis fighters or provided the militant organisation with "logistical aid or helping them carry out terrorist attacks", the judge's statement said. Daesh is the acronym for the Arabic name of the terrorist group. Verdicts may be subject to appeals.
According to Human Rights Watch (HRW), several women of different nationalities along with the ISIS fighters have surrendered to the Iraqi forces.
Thousands of foreigners have fought for the Islamic State group in Iraq and Syria since 2014.
Also on Thursday, an Iraqi newspaper reported that more than 1,500 foreign women and children from the families of IS militants are being held by the Iraqi authorities, which are coordinating with the countries of origin to decide their fate.
In January, a court sentenced a German woman to death on charges of providing logistical support to IS, and a Turkish woman was earlier this month also handed the death penalty. In total, officials estimate that more than 20,000 people are being held in prison for membership to a terrorist organization.
Human Rights Watch has raised concerns about the judicial process and branded the trials unfair.
Iraq has sentenced 16 Turkish women to death for involvement with ISIS. Iraq in December declared victory over the IS, which had seized control of almost a third of the country in 2014. The suspects claimed to have been tricked into joining ISIS militants.
"The Iraqi government has valid security concerns that ISIS members sought for serious crimes should not be able to get fake identity documents", Fakih said.