The quasi-totality of social scientists who studied screening for cervical tumours identified such screening with a single method: the Pap smear (exfoliative cytology). This article explains that this method was not valid everywhere. The history of screening for cervical cancer in Brazil displays an alternative method for detecting cervical malignancies: a direct observation of the cervix with a specific instrument — the colposcope. The development of this method in Brazil in the 1940s and 1950s reflected a complex mixture of professional interests, government policies, and regional, local and charitable initiatives. While the use of colposcopy for cervical tumour screening was phased out in the 1970s and 1980s, the long lifespan and widespread diffusion of this method illuminates the irreducible contingency of specific developments in science, technology and medicine. Seen from the vantage point of Brazil, the Western model for preventing cervical malignancies no longer appears self-evident. Alternative choices might have led to the development of different material and visual cultures of medicine, stimulated different patterns of medical specialization and division of medical labour, produced different links between malignancies, women, gynaecologists, epidemiologists and public health experts, and shaped different health policies.