Wives and Handmaids

That's a good question.....and I have no idea.

I think most (if not all) of the Commanders were already married at that point. And we know how these types of religious people feel about divorce. Also, lots of people wanting babies, not enough women (and men) that can have them. If you marry a Handmaid, you're limiting the chanses for creating the next generation, which is their big thing in Gilead. So you breed with one and you pass her to the next misfortunate family unit. Basically, Handmaids are breeding stock.

Also, it may be that the wives are not barren at all. Just stuck with sterile husbands and way too pious and obedient to look for pregnancy opportunities elsewhere.

I think Serena was smart enough to know this. I think a lot of her simmering resentment and frustration came from suspectimg that she may actually be fertile, but because of the messed-up world that she helped to create, she will never know.

They imply that whatever chemical weapons they used to fight the war rendered the men in power either sterile or with compromised fertility. The toxicity of the chemical weapons is reinforced by how poisonous the colonies are.

Because of the Old Testament patriarchical nature of the society, the assumption is that if a couple can't conceive, it must be the fault of the woman (see the Old Testament stories of Abraham, Isaac, and the New Testament story of Elizabeth and Zachariah). The wives suspect that it's not their fault so some of them make other arrangements to get the handmaids pregnant. That's the reason the gynecologist offers to impregnate June and Serena arranges for her to have sex with Nick.

The way I understood it, the average woman could no longer bear children. While people would still get married it was the responsibility of the handmaids, woman who could still bear children, to provide the families with babies.