What i want to know, is do they use women who already have a child inside, or impregnate them once they are taken?

At least this gives more evidence they are not zombies: they can reproduce, to an extent, and are able to grow further than where they were changed. I also like how they didn't give a full description of the body, so we can't guess if it was Samantha. But then, would hair still be pigmented after 9 months of decomposition/mummification?