In the most modern parts of the modern world, three aspects of fertility do seem historically unprecedented and clearly important. First, there is no stigma attached to being childless; a woman’s worth, in this life or the next, is not judged adversely if she chooses never to have children. Second, children are no longer economic assets, as they generally were in rural and early industrial societies; rather, they are economic burdens, voracious consumers who produce virtually nothing until their late teens or early twenties. Third, fertility control is now both uneventful and virtually absolute. Those who want to avoid having children can easily do so–without restraining their natural sex drive, without putting themselves at physical risk, and without resorting to infanticide or abortion.
Children are thus culturally optional, economically burdensome, and technologically avoidable. Still, having the option to avoid children is not a reason to avoid them, and for many, clearly, the economic burdens seem bearable enough. So the question remains: why do so many men and women in the most affluent societies in history seem to want so few offspring?