Garaad diinle
I forgot to add if a slave gets pregnant her status elevates and the master is not allowed to sell her and as i said her children are free but i also recall that she also becomes free.I don't know if i'm qualified to answer this question one must admit their lack of knowledge but i'l share what i know. First of there isn't anything about this in quran and sunnah as far as i know. The rules of war in islam is as follows.
"You will find a people who claim to have totally given themselves to God. Leave them to what they claim to have given themselves… Do not kill women or children or an aged, infirm person. Do not cut down fruit-bearing trees. Do not destroy an inhabited place. Do not slaughter sheep or camels except for food. Do not burn bees and do not scatter them. Do not steal from the spoils, and do not be cowardly"
As you can see there is no such thing as the r word included. What your talking about is most likely is slavery in islam. The prisoner of war if not ransomed or freed by he who caught them are sold as slaves. Islam didn't have prisons so what they did with the captive is sell them to people were they worked under their master or prisoner much like prison labour.
What about the women. As i said i'm not very knowledgeable so you may read further on the topic. I read that the men must ask for permission to engage in intercourse and i read in another place that the women are seen as have been forcefully married to their master so they are considered a pseudo wife with less right for example they don't get maher but her children are free and not slaves where as in other cultures the children would also be seen as slaves.
conclusion.
So slavery is capitalism where prisons are privatized where everyone can get a prisoner for a price and the prisoner would do prison labour unless the prisoner wanna free himself at that point he would have to sign a contract with the master to free himself. Same goes for women with the sole exception that they're seen as pseudo wife with less rights than a free wife but her children if they're the children of the master are free children. Keep in mind slavery wasn't introduced by islam and was practiced by every single culture out there including christianity and judaism. Islam infact curbed down on many forms of slavery such as kidnap slaver, debt slavery or simply selling a free person.
There are rules as to how to treat a slaves in islam the prophet ﷺ said.
They are your brothers whom Allah has put under your authority, so if Allah has put a person’s brother under his authority, let him feed him from what he eats and clothe him from what he wears, and let him not overburden him with work, and if he does overburden him with work, then let him help him.” [Bukhari 6050]
Slaves in islam became statesmen sultans and military commanders at some point. Many early esteemed muslim scholars that are respected were slaves themselves.