Objectives: To evaluate prenatal screening methods for Down syndrome and neural tube defects (NTD) with regard to costs per detected case and the number of screening-related miscarriages. Methods: The screening methods compared were risk assessment tests, i.e. serum tests and nuchal translucency measurement (NT), and invasive testing through chorionic villus sampling (CVS) or amniocentesis. Costs, the number of cases detected and screening-related miscarriages were calculated using a decision tree model. Results: The costs per detected case of Down syndrome ranged from EUR 98,000 for the first-trimester (serum) double test to EUR 191,000 for invasive testing. If NTD detection was included, the (serum) triple test had the lowest costs, EUR 73,000, per detected case of Down syndrome or NTD. The number of screening-related miscarriages due to invasive diagnostic tests varied from 13 per 100,000 women for the (serum) first- and second-trimester combined test to 914 per 100,000 women for invasive testing. Conclusions: Considering screening for both Down syndrome and NTD favors the triple test in terms of costs per detected case. Compared to invasive testing, risk assessment tests in general substantially lower screening-related miscarriages, which raises the question of whether invasive testing should still be offered in a screening program for Down syndrome.