Blame Karl

In colonial New England the birth rate averaged over seven children per woman of childbearing age. Men and women needed the labor of children. Producing offspring was as necessary for survival as producing grain. Sex was harnessed to procreation. […] By the 1970s, however, the birth rate had dropped to under two. With the exception of the postWorld War II baby boom, the decline has been continuous for two centuries, paralleling the spread of capitalist relations of production. It occurred when access to contraceptive devices and abortion was systematically curtailed. The decline has included every segment of the population – urban and rural families, blacks and whites, ethnics and WASPS, the middle class and the working class. As wage labor spread and production became socialized, then, it became possible to release sexuality from the ‘imperative’ to procreate. Ideologically, heterosexual expression came to be a means of establishing intimacy, promoting happiness, and experiencing pleasure. In divesting the household of its economic independence and fostering the separation of sexuality from procreation, capitalism has created conditions that allow some men and women to organize a personal life around their erotic/emotional attraction to their own sex. (d'emilio)