The prenatal diagnosis of Down syndrome (amniocentesis) presents parents with a complex dilemma which requires comparing the risk of giving birth to an affected child and the risk of losing an unaffected child through amniocentesis-related miscarriage. Building on the specific features of the French Health insurance system, this paper shows that variation in the monetary costs of the diagnosis procedure may have a very significant impact on how parents solve this ethical dilemma. The French institutions make it possible to compare otherwise similar women facing very different reimbursement schemes and we find that eligibility to full reimbursement has a largely positive effect on the probability of taking an amniocentesis test. By contrast, the sole fact of being labelled 'high-risk' by the Health system seems to have, as such, only a modest effect on subsequent choices.