The cost effectiveness of prenatal ultrasound screening for trisomy 21

Objectives: To compare the cost effectiveness of opportunistic nuchal translucency ultrasound screening in pregnancy with alternative screening strategies for trisomy 21 in Australia. Methods: A decision analytic model of various pregnancy screening strategies based on a systematic review of the literature on the effectiveness of nuchal translucency ultrasound and serum screening and costs based on current reimbursement fees. The model included the likelihood and cost of terminations following diagnostic testing and the associated risk of fetal loss. All prices are in 2001 Australian dollars Results: With a twenty percentage point difference in detection rate the incremental cost for a combination of nuchal translucency and serum screening with age in first trimester compared to maternal serum screening in the second trimester was $105,484 per extra case detected and $374,779 per live trisomy 21 birth avoided. Serum screening in the second trimester had an incremental cost per extra case detected of between $61,700 and $117,100 per extra live birth avoided when compared with no screening. Conclusions: The economic analysis is limited by the perspective taken and has not been able to include some of the attributes of a screening program such as reassurance and impact on the family and society of a trisomy 21 birth. Nevertheless the cost effectiveness of ultrasound screening would appear to be more attractive if it was done at the same time as current dating ultrasound. Any funding mechanism for screening should take this into account by incorporating as far as possible, provision of nuchal translucency screening into existing services provided in early pregnancy.