Most of the ideas that spawned the Quiverfull movement can be traced to books like The Way Home by Mary Pride (key quote: "My body is not my own"), an anti-feminist treatise published way back in the ancient days of 1985, when men were RoboCops and women wore shoulder pads. The first wave of Quiverfull families weren't born into anything. Like roughly 2/3 of people who join cults, they came into it as young adults fleeing shitty childhoods. Choosing this alternative lifestyle was their rejection of the "normal" world -- whether they were fleeing drug abuse, alcohol abuse, or plain vanilla no-frills physical abuse -- to right the wrongs of their parents. And for some reason they thought the best way to do that was to have kids the way other people buy Costco cheese.
No, seriously. Here's the basic political idea behind the Quiverfull movement: The more babies we have, the more voting Christians we'll have to balance out the heathens. The individual babies really aren't as important as the quantity you successfully indoctrinate into the cause.
Way to really half-uterus it.