The New York Times is reporting that Islamic State radicals are using contraception to ensure enslaved women do not become pregnant and can be passed among its fighters as sex slaves.
The report released on March 12 adds to other mounting evidence of organized, wide-scale sexual crimes being committed by the extremist group as it tries to organize a religious state in captured territories in Syria and Iraq.
The newspaper interviewed more than three dozen Yazidi women who escaped from the militant group.
The paper cited a gynecologist who examined the women and found only a small percentage had become pregnant during their enslavement.
Thousands of Yazidis were captured by Islamic State militants when they overran northern Iraq; the group considers Yazidis to be devil-worshippers.
The United Nations and human rights groups have accused the Islamic State of the systematic abduction and rape of thousands of women and girls as young as 12.
Many have been given to fighters as a reward or sold as sex slaves.