In 2017 the Belgian government adopted a law allowing all pregnant women to perform a NIPT test from 12th week of pregnancy to detect foetal risk of trisomy 21. Performing an NIPT test was then no longer the matter of genetic centres but a routine test performed in medical laboratories those must be licensed and accredited ISO15189 to perform NIPT testing.

As licensing and accreditation are linked to the participation to EQA, the department Quality of laboratories of Sciensano (national EQA organizer) has launched an NIPT EQA in 2020. In first instance this EQA was organized in collaboration with GenQA and laboratories were registered to their NIPT scheme. It quickly became an evidence that this scheme should be entirely organized by our department self in order to i) monitor closely the performance of laboratories, ii) assessing the extra-analytical phases and iii) to reduce the costs.

In 2022, the first Belgian NIPT EQA was launched using commercially available 1mL simulated plasma samples with encapsulated foetal DNA carrying the chromosomal aneuploidy. The sample was accompanied by clinical data such as patient name, surname, address, date of birth, patient weight and height, gestational age, number of foetuses, due date and patient clinical history. Laboratories were asked to analyse the sample and send us their clinical report. Those were then screened for completeness to national guidelines: identification of the patient, report of trisomy 21 in terms of high risk/low risk, invasive test obligation in case of high risk, date of sample collection, date of sample reception and date of report.

14 medical laboratories have participated in 2022 and 2023 for 15 medical laboratories in the round of 2024.  In 2024, all laboratories reported the high risk of Trisomy 21 and the obligation of an invasive test as confirmation in comparison to previous years. Indeed, in 2022, 1 laboratory didn’t report a risk of trisomy but a suspicion of chromosomal anomalies and neither reported an obligation of an invasive test as confirmation. In 2023, this laboratory still reported the trisomy in terms of suspicion but reported the obligation of an invasive test. Besides, another laboratory reported a detection of trisomy 21 with a positive predictive value in 2022 and 2023 but didn’t not clearly report it as high risk/probability. With regards to the completeness of the clinical reports with the Belgian Clinical Biology practice guideline (1), 7 laboratories reported an incorrect sample collection date in 2022 and only 4 in 2023. In 2024, 5 laboratories reported an incorrect collection date and 1 did not mentioned the date of the report.

Implementing a NIPT EQA in Belgium allows us to detect some failure of laboratories when reporting NIPT results in accordance with Belgian (2) and European (3) guidelines. With years, laboratories have improved and adapted their protocol which reinforce the usefulness of such EQA schemes.