Women’s preferences for antenatal screening for Down syndrome in Northern Ireland: a choice experiment

Background. Despite an increasing international trend towards the implementation of antenatal screening programmes for Down syndrome, there is currently limited information relating to women’s choices or preferences for such screening. Information about women’s preferences for and insight into the potential value they may derive from any change to screening programme design are essential components of evidence-based policy decision-making. This paper reports on a choice experiment undertaken to examine the preferences of a sample of pregnant and non-pregnant women of childbearing age with respect to antenatal screening for Down syndrome in Northern Ireland, where the offer of screening is not universal and selective abortion on the grounds of fetal abnormality is legally inaccessible. Method. The choice experiment was conducted using an internet-based survey to obtain the preferences of a volunteer sample of 50 pregnant and 73 non-pregnant women for screening tests that varied according to six test characteristics or attributes derived from an earlier focused ethnographic study. These attributes were: source of screening information, time of test in pregnancy, accuracy of test results, cost of test as an ‘out-of-pocket’ expense, waiting time for test results, and risk of miscarrying a baby unaffected by Down syndrome as a result of subsequent diagnostic testing. Results. Pregnant and non-pregnant women prefer screening tests for Down syndrome offering results with accuracy levels of 90% and above, and where the risk of subsequent diagnostic procedure-associated miscarriage is 2% and below. Women preferred screening tests offering more accurate results over no risk of miscarriage. Pregnant women place more value than non-pregnant women on tests carried out during the first trimester. Conclusion. Policies for the implementation of antenatal screening programmes for Down syndrome must consider the preferences of pregnant and non-pregnant women to ensure that the needs of current and potential future service users are met. Effective pre-test counselling is essential to ensure that women understand the attributes of any screening test and its possible implications.