AbstractThis essay uses Predictor, the first home pregnancy test, to reexamine the doctor-patient relationship in Britain in the 1960s and 1970s, a tumultuous period associated with permissiveness, women's liberation, and the erosion of medical authority. It shows how the rise of self-testing contributed to a realignment of the power dynamics among women, doctors, and pharmacists. It argues that the humble home pregnancy test kit merits a place—alongside the birth control pill and abortion law reform—in histories of health consumerism and reproductive choice in the twentieth century.