Amid wider efforts to improve maternal and infant health in Britain around the First World War, public health officials debated making pregnancy a notifiable condition. Although the policy never entered national legislation, a number of local authorities introduced 'notification of pregnancy' schemes in various guises, with at least one surviving until the 1950s. Resistance from private practitioners to infectious diseases notification in the later nineteenth century has been well documented. We know less about opposition to the extension of this measure to maternal and infant welfare, especially from newly professionalising female health occupations. Conflict over notification of pregnancy drew midwives, in particular, into longstanding arguments over the powers of municipal authorities, family privacy and professional ethics. The controversy was the key battleground in negotiations over the organisation of 'antenatal care' as occupational groups of varying degrees of authority sought to define their roles and responsibilities within the emerging health services.