Part of this can be attributed to the fact that ISIS takes anyone, and there are many roles in the proclaimed caliphate (religious-based state) that women can play, said Magnus Ranstorp, a terrorism expert who serves as quality manager of the European Union Radicalisation Awareness Network.And ISIS recruits are young, averaging just 22 years old among the Western women, according to New America. Some are in their teens, like 19-year-old Shannon Conley from Colorado, who authorities say planned to travel to Syria. Conley was convicted and sentenced to four years in a federal prison. For her part, Conley told the judge that she never intended to cause harm, according to The Denver Post.

The London-based ISD study, "Till Martyrdom Do Us Part" looked at why women and girls were being recruited, the diversity of roles they take on, and how to combat the threat. The picture is more complex than the "jihadi bride" label often attributed to them. For their study, ISD tracked more than 100 Western women across online platforms like Twitter, Facebook, and Tumblr.Women can be pushed to join ISIS because they feel isolated, persecuted, or they feel an anger or sadness about perceived lack of international action against injustice. According to ISD, they might also be drawn or pulled by idealistic goals about building a caliphate; want to belong to a sisterhood; or glamorise what their experience with ISIS might be like. The women who are attracted to the fight hail from a variety of cultural, ethnic, educational, and religious upbringings.