After initial misunderstandings regarding the performance of the NIPT could be cleared up (Eiben et al. 2024), the main criticism of the test in Germany is now that it is recommended to pregnant women regardless of medical relevance. These concerns relate primarily to younger women, who are allegedly prescribed NIPT despite a low prior risk of the three aneuploidies eligible for statutory reimbursement. However, our results suggest that there is currently no evidence of a specifically (and unjustly) increased tendency of younger pregnant woman in Germany to undergo NIPT for trisomies 21, 18 and 13. Therefore, any allegations that women are pressured by their doctors to do so are most likely unjustified. The latter conclusion is further supported by a recent survey in Germany (von Ostrowsky et al. 2025) in which only 6% of respondents reported that they felt influenced by their doctor in their decision-making for or against NIPT.

A recent study confirmed that, while NIPT has gained global acceptance, its national uptake figures vary widely depending upon previous and current screening practices, the actual design of the test (e.g., first-tier or second-tier), its out-of-pocket costs, and its cultural and health policy framework. Consequently, the NIPT uptake may be as low as 1.5% in Ontario, Canada (first-tier, women ≥ 40 years), and as high as 93.2% in Andalusia, Spain (second-tier, high-risk pregnancies only) (Sebire et al. 2024). To validate the decision theory-based approach of our work, it would thus be helpful to compare NIPT uptake in Germany with that in countries where comprehensive NIPT is offered as a nationwide screening not limited to aberrations with age-dependent risk.

In the Netherlands, NIPT was implemented from the outset as a national screening program that covers trisomies 21, 18 and 13, but that also targets other numerical and structural chromosomal aberrations, depending upon the women’s wishes (van der Meij 2019). The first age-specific NIPT uptake figures were reported for the Netherlands, in 2019, to equal q1 = 0.21, q2 = 0.48, and q3 = 0.55 in neighborhoods that were not specifically disadvantaged (van der Meij et al. 2021). With these numbers, the theoretically inferred cost assignments would closely resemble those of German women in age groups 1 and 2 (Fig. 2). Above the age of 35 years, however, the slope of the corresponding (red) line was substantially smaller for Dutch women than for German women of today, apparently indicating lower relative costs C assigned to delivering and raising a trisomic child. Worthy of note, monetary test costs in the Netherlands had to be partly covered out-of-pocket in 2019 (at 175 Euros), which could have increased CN and decreased C in age group 3 as well.

Inferred age-specific relationship between the mean (µ) and standard deviation (σ) of the relative trisomy costs (C) assigned by Dutch women. Solid lines: 2019 data, dotted lines: 2023 data. For details, see legend to Fig. 1

In any case, by 2023, the NIPT uptake figures in the Netherlands had increased to q’1=0.46, q’2=0.70, and q’3=0.71 (Radboud University Medical Center 2025). With these new numbers, the slopes of all three lines increased dramatically and exceeded those of their German counterparts for age groups 1 and 2 (Fig. 2). There was thus either a significant increase in relative trisomy costs C among Dutch women, or the decision-making process no longer followed the presumed decision theory model because age-specific prior risks were increasingly neglected.

The latter explanation seems rather likely because, whereas invasive testing was no longer offered to Dutch women ≥ 36 years from 2014 onwards, NIPT was introduced in the Netherlands in 2017 as a first-tier test that also covered age-independent structural chromosomal aberrations. This means that, while pregnant women also receive pre-test counselling in the Netherlands, maternal age has become a poorer predictor of a true-positive test result than in Germany and may hence no longer have played an important role in the counseling and decision-making of Dutch women about NIPT (van der Meij et al. 2019). In fact, in a 2018 survey of 600 Dutch women who underwent NIPT, only 1% of participants cited the perception of a high trisomy 21 risk as their main reason to do so (van der Meij et al. 2019; Meij et al. 2022).

Regardless of the plausibility of the above, an increase of the relative trisomy costs C could also apply, at least in part, to Dutch woman. In the quoted survey, 64% of participants thus expressed that they considered Down syndrome to be a serious condition, and 71% would have found it a great burden to raise a child with Down syndrome (van der Meij et al. 2022). Finally, NIPT is fully reimbursed in the Netherlands since April 2023 so that the test costs CN decreased, and the relative costs C = CT/CN increased, in all age groups.

In conclusion, the current NIPT uptake in Germany corresponds well to the age-specific prior risks of trisomies 21, 18 and 13, i.e. the three aneuploidies for which the test costs are reimbursed by the statutory health insurance. The validity of this claim is supported by its lack of transferability to the Netherlands, a country with a fairly similar cultural background to Germany, but with a clear violation of the underlying decision theory model due to the inherent independence of decision-making from the respective prior risks. Therefore, the political discussion on NIPT in Germany should refrain from implying that the test is recommended to pregnant women regardless of medical relevance which, in Germany, relates mainly to advanced maternal age. Replication of our analysis in other countries will reveal whether the consistency between age-specific prior risk and NIPT uptake observed in Germany is unique, or whether it also exists in other healthcare systems. Furthermore, we recommend continuous monitoring of the uptake in Germany itself to determine whether the current age-specific pattern is a temporary feature of the NIPT implementation phase or a more permanent feature of the national context.