Objective
To analyse the cost‐effectiveness and performance of noninvasive prenatal testing (NIPT) for high‐risk pregnancies following first‐trimester screening compared with current practice.

Methods
A decision tree analysis was used to compare the costs and benefits of current practice of first‐trimester screening with a testing pathway incorporating NIPT. We applied the model to 32 478 singleton pregnancies screened between January 2005 and December 2006, adding Medicare rebate data as a measure of public health system costs. The analyses reflect the actual uptake of screening and diagnostic testing and pregnancy outcomes in this cohort.

Results
The introduction of NIPT would reduce the number of invasive diagnostic procedures and procedure‐related fetal losses in high‐risk women by 88%. If NIPT was adopted by all women identified as high risk by first‐trimester combined screening, up to 7 additional Down syndrome fetuses could be confirmed. The cost per trisomy 21 case confirmed, including NIPT was 9.7% higher ($56 360) than the current prenatal testing strategy ($51 372) at a total cost of $3.91 million compared with $3.57 million over 2 years.

Conclusion
Based on the uptake of screening and diagnostic testing in a retrospective cohort of first‐trimester screening in Western Australia, the implementation of NIPT would reduce the number of invasive diagnostic tests and the number of procedure‐related fetal losses and increase the cost by 9.7% over two years. Policy planning and guidelines are urgently required to manage the funding and demand for NIPT services in Australia.