I am a gynecologist

The approach to extensive genetic testing with rare aneuploidies and microdeletions yielded a high sensitivity of 96.4% and a speci city of 99.8% for rare aneuploidies and a sensitivity of 74.1% and a speci city of 99.8% for microdeletions greater than 7 MB.

The Illumina Veriseq NIPT Solution uses extended genome sequencing to provide a comprehensive view of the genetic material. This provides a wealth of information across the entire genome, effectively removing interference introduced by molecular techniques such as PCR. Targeted sequencing and plate-based methods tend to have longer laboratory protocols and employ more PCR cycles than genomic methods, introducing potential sources of error and increasing interference. This lack of coverage can be further increased when working with more challenging samples such as those with lower percentages of fetal fractions. In these cases, the information does not differ enough for the test to provide a reliable result on one side or the other (aneuploidy or disomy).

In a very limited number of cases, the Prequel® test cannot be administered successfully. This usually occurs when the amount of fetal DNA (cffDNA) is too small to provide a result. Other reasons for test failure include failure to report the presence of a donated egg, the presence of a resorbed twin and previously undiagnosed chromosomal abnormalities (usually benign) in the mother.
In such cases, we recommend that venous blood from the mother be drawn again at a slightly later stage of the pregnancy to repeat the Prequel® test. The majority of cases have been successfully processed after a repeat blood sampling.

If the test is not performed successfully after a repeat sampling, the customer will be fully refunded. 24 hours must have elapsed since the last administration of low molecular weight heparin therapy.

Mosaicisms, partial trisomies and translocations

No NIPT method based on the cffDNA test can detect chromosomal mosaicism, partial trisomy or translocations.

Multiple pregnancies

Prequel® cannot be used to test for chromosomal abnormalities in 3 or more fetuses. In case of triplets and multiple pregnancies, invasive methods are recommended.

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