Nesting is a hormonally-determined set of behaviours, observed in some animals, relating to the preparation of the space in which the offspring will be born and raised. Texts on childbirth and pregnancy advise women that they will experience nesting behaviours during pregnancy, causing them to tidy, clean, and prepare their living space. In this paper, I analyse the discussion of nesting behaviours on popular pregnancy websites. I then investigate the evidence base for nesting in humans through conducting a systematic review of the academic literature, and conclude that it is inadequate to ground the claims made in the popular discourse. The article concludes by presenting social explanations for nesting behaviours which are more plausible than the proposed biological narrative. These explanations make reference to the influence of gender stereotypes and the specific pressures experienced by women during pregnancy.