Well, they'd have to not rape the women to death first. Then not kill the kids before, during, or after they're born. I really don't see that happening.
In fact, whenever shows/movies have had Reaver-type societies, I've never understood how the society lasted. Since they're all ready to kill, how do they get along long enough to do anything, let alone fly a damn spaceship? Is someone in charge? Do the "recognize" each other and so don't kill each other? A simple line, "They don't kill their own" would at least "explain" why there's some
stability in their society.