The cost effectiveness of prenatal ultrasound screening for trisomy 21.

Objectives: The cost-effectiveness of opportunistic nuchal translucency ultrasound screening in pregnancy was compared with alternative screening strategies for trisomy 21 in Australia.

Methods: A decision analytic model was used 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 after 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 the first trimester compared with maternal serum screening in the second trimester was 105,484 dollars per extra case detected and 374,779 dollars per live trisomy 21 birth avoided. Serum screening in the second trimester had an incremental cost per extra case detected of between 61,700 dollars and 117,100 dollars per extra live birth avoided when compared with no screening.

Conclusions: The cost-effectiveness of ultrasound screening for trisomy 21 would appear to be more attractive if it were done at the same time as current dating ultrasound. Any funding mechanism for screening should take this strategy into account by incorporating, as far as possible, provision of nuchal translucency screening into existing services provided in early pregnancy.