Limited noninvasive prenatal testing (NIPT)
Vasistera™ NIPT is a blood-based genetic, prenatal screening test of the pregnant person that screens for common chromosomal conditions that affect a baby’s health. Vasistera screens for trisomy 21, trisomy 18, and trisomy 13. Fetal sex reporting is optional. Vasistera can be performed as early as ten weeks gestation. Most results will be returned to your doctor within 5-7 calendar days.
Like Panorama™, our company’s market-leading NIPT, Vasistera™ NIPT leverages Natera’s unique SNP*-based methodology to analyze cell-free DNA. Unlike Panorama™, Vasistera™ NIPT does not report other chromosomal conditions, such as triploidy, sex chromosome aneuploidies, or microdeletions such as 22q11.2 deletion syndrome.
Vasistera™ NIPT is a screening test, which means that this test does not make a final diagnosis. A screen positive result means that your pregnancy has a higher chance of having a specific genetic condition. However, you cannot know for sure if your baby has that condition based upon the screening result alone. All medical decisions should be made after discussion with your clinician regarding diagnostic testing during the pregnancy, like chorionic villus sampling (CVS) or amniocentesis, or testing the baby after birth.
*SNP, single nucleotide polymorphism
Find out how Natera’s prenatal screening tests, including Vasistera™, helps identify your baby’s risk of having a genetic condition
Complete Test Specifications for Singleton, Egg Donor, Gestational Carrier, and Monozygotic (Identical) Twins
Definition of performance terms
Sensitivity is the ability to correctly identify a truly positive case as positive. For example, in a group of Trisomy 21 cases, Vasistera™ NIPT will correctly identify more than 99% of those cases.
Specificity is the ability to correctly identify an unaffected case as negative.
Positive Predictive Value (PPV) is the likelihood the result says screen positive and the fetus is actually affected. For example, when Vasistera™ NIPT shows a screen positive result for Trisomy 21, there is a 95% chance that the fetus is affected by Trisomy 21. In other words, 5% of the time, you could get a screen positive result when the fetus is not affected by Trisomy 21.
Negative Predictive Value (NPV) is the likelihood the result says screen negative and the fetus is truly not affected.
|Condition||Sensitivity (95% CI)||Specificity (95% CI)||PPV||NPV|
|Trisomy 212,3||99.0% (CI 97.1-100)||>99% (CI 99.93-99.99)||95%||>99.99%*|
|Trisomy 182,3||94.1% (CI 82.9-100)||>99% (CI 99.96-100)||91%||>99.99%*|
|Trisomy 132,3||>99% (CI 73.5-100)||>99% (CI 99.96-100)||68%||>99.99%*|
|Female4,5,6||>99.9% (CI 99.4-100)||>99.9% (CI 99.5-100)|
|Male4,5,6||>99.9% (CI 99.5-100)||>99.9% (CI 99.4-100)|
Test Specifications for Dizygotic (Nonidentical) Twins7
1ACOG Practice Bulletin 226. Obstet Gynecol. 2020 Oct;136(4):859-867.
2Dar et al. Am J Obstet Gynecol. 2022 Aug;227(2):259.e1-259.e14.
3DiNonno et al. J Clin Med. 2019 Aug 26;8(9):1311.
4Nicolaides et al. Prenat Diagn. 2013 June;33(6):575-9.
5Pergament et al. Obstet Gynecol. 2014 Aug;124(2 Pt 1):210-8.
6Ryan et al. Fetal Diagn Ther. 2016;40(3):219-223.
7Natera internal data on file.
* Ongoing clinical follow-up is performed to ensure the NPV does not fall below the quoted value but follow up is not obtained for all low risk or screen negative calls.