Down s syndrome is one of the most common chromosomal abnormalities in the UK. The availability of different screening and diagnostic options along with difficulties for couples in understanding the concept of risk and interpreting test results can complicate the decision-making process for women. The aim of our study was to examine the main concerns of women in deciding about the screening and diagnostic tests for Down s that they would undergo during the antenatal period. Knowledge of women s concerns informed the development of a Decision support system that aims to help women choose the option that most respects their personal values.