The non-invasive prenatal test (NIPT) was introduced in the North Denmark Region in March 2013. NIPT is offered as an alternative to invasive tests if the combined first trimester risk of trisomy 21 (T21) is = 1:300. The purpose of this study was to investigate the effect of NIPT implementation among high-risk pregnancies in a region with existing first-trimester combined screening for T21. The primary objective was to examine the effect on the invasive testing rate.
This was a retrospective observational study including high-risk singleton pregnancies in the North Denmark Region. The women were included in two periods, i.e. before and after the implementation of NIPT, respectively. Group 1 (before NIPT): n = 253 and Group 2 (after NIPT): n = 302.
After NIPT implementation, the invasive testing rate fell from 70% to 48% (p