Test Focus

Cell free DNA screening for trisomy 13, 18, 21

Cerba was the first laboratory in europe to provide cell free DNA screening for trisomy 13, 18, 21.

First laboratory in Europe to provide Cell Free DNA Screening

Our experience of more than 3 years of practice, and the realization of more than 25,000 tests in clinical routine or in the framework of research projects (SEHDA * studies published in June 2015, Obstet Gynecol 2015; 125: 1330-7 , DEPOSA and NIMAP), demonstrate the performance and interest of this test.

In June 2017, we changed our offer with the introduction of the Illumina VeriSeq NIPT test.

The results of a clinical validation study conducted on more than 3,500 patients confirmed the exceptional performance of this new screening approach for trisomy 13, 18 and 21 with a sensitivity and specificity of more than 99%. An internal evaluation also showed a perfect correlation with the test previously used by our laboratory since November 2013.

Cell free DNA screening for trisomy 13, 18, 21 indications

The cell free DNA screening for trisomy 13, 18 and 21 is open to all pregnant women without signs at ultrasound scan (especially nuchal translucency superior or equal to 3.5 mm) and is recommended in the following cases:

1.Primary screening (maternal serum screening not perfomed yet)
2.Maternal serum screening with risk of fetal trisomy 21 higher than 1/1000 whatever the maternal serum screening strategy
3.Patient age above 35 that could not benefit from maternal serum screening.
4.Parental robertsonian translocation involving chromosome 21.
5.Patient with prior medical history of fetal aneuploidy.
6.Twin pregnancy 7. Patient in whom maternal serum screening is not consistant (serum markers out of cut off values)

It can be performed all along the pregnancy but must not be performed before the 10th week of gestation and is recommended after Q1 ultrasound scan (11-14 WA).


The usual turnaround time ranges from 5 to 10 working days at reception of the specimen at Laboratoire Cerba. Performing this test, regardless its result, does not replace in any case the follow-up of the pregnancy by ultrasound scan.