By the turn of the twentieth century the British nation’s declining birthrate was increasingly the subject of anxious public and scientific debate, as the Registrar General’s annual reports continued to confirm a downward national trend, which had in fact commenced from the late 1870s. The secularist Malthusian League had positively promoted birth control, and now economists and eugenicists, feminists and Fabians, as well as leading figures in the church and in the medical profession, all agreed that this was a momentous matter. Previously, human fecundity—the capacity to conceive and reproduce—had not been considered a significant social variable. While the fertility of individuals or couples might be subject to some variation, with the od...