"When directly confronted, in a polemical context, with historical and textual permission for the sexual use of unfree women, Muslim authors sometimes respond defensively, seeking to protect Islam’s reputation. It may be argued, for instance, that Islamic “slavery” bore no resemblance to harsh American chattel slavery. In this view, the Qur’anic permission for men to have sex with “what their right hands possess” was merely a way of integrating war captives into society. Sometimes, it is added that the captives would be “integrated” into the Muslim community through becoming the property of a specific man who would be responsible for them and their offspring. Whatever merit these arguments have in the context of inter-communal polemics and apologetics, however, they are insufficient for internal Muslim reflection. In particular, the notion that women would be integrated into society by bearing offspring to their owners or captors does not apply to the case of the Bani Mustaliq: the rationale for the captors to practice withdrawal, according to other accounts, is that they did not want to impregnate the women lest they spoil their chances to ransom them."
January 1, 1970
https://en.wikiquote.org/wiki/Islamic_views_on_concubinage