Non-rare thrombophilia (NRT) are hereditary predispositions to thromboembolism, the most severe side effect of combined hormonalcontraception. In the mid-1990s, theidentification of NRT stirred up acontroversy over the possibility of investigating these genetic variants inwomen wishing to use contraception. Through a review of literature, thisarticle reconstructs the debate over whether and how this genetic test shouldbe prescribed as a way to reconfigure the risk visibility on pharmacologicalcontraception. The mainarguments identified concern the epidemiological,social, economic and clinical aspects of the test. In a context where theoverall thrombotic risk for hormonal contraception is largelyinvisible, thegenetic tests turn to embody the thrombotic risk itself. Those who opt forselective screening argue that a better estimation of risk implies a testprescription embed in aglobal medical assessment of women’s individual risk.To advocates of universal or ‘extended’ screening, the tests are valuable toolsto inform women on the thrombotic risk and, assuch, appraised as a moral/legalobligation, whatever their predictive power. Risk visibility thus appears as aninsightful concept to analyse a complex setting associating clinical,political, social and cultural considerations that touches upon medical power,women’s responsibility and drug safety.