Compare procedure-related loss with the chance diagnostic testing finds trisomy 21, 18 or 13 after NIPT.
CVS or amniocentesis collects the sample, but microarray is a separate laboratory test and is not always included.
Change the procedure-loss estimate
The input starts with the ACOG US patient-information default for the selected procedure. Replace it with your clinic’s estimate if you have one.
Change NIPT or starting-chance details
Age-based default
Age-based default
Age-based default
The defaults are population estimates for a standard NIPT. Use a report or clinician-provided value if it better reflects your test or pregnancy.
Change the microarray finding estimate
The age-group default is 1 in 145 below age 35 and 1 in 73 at age 35 or older. Replace it if a genetics professional gives you a more relevant estimate.
Estimated context after NIPT
22q11.2 deletion syndrome, 1p36 deletion syndrome and 5p deletion syndrome (Cri-du-chat) are examples, not the three most likely findings.
Sources and how they were used
- ACOG amniocentesis guidance: The default procedure-related loss estimates are ACOG's US patient-information figures: about 1 in 455 for CVS and 1 in 900 for amniocentesis. They are broad defaults, not an individual clinic prediction.
- SMFM Consult Series #74: Supplies the default sensitivity values for a standard NIPT for trisomy 21, 18 and 13.
- Genetic Support Foundation NIPT Predictive Value Calculator: Supplies the age-based starting chances at about 16 weeks and the predictive-value approach used for low-risk and high-risk NIPT results.
- Maya et al. 2022: Supplies the age-group defaults for clinically significant copy-number findings remaining after theoretically excluding standard T21/T18/T13 NIPT-detectable findings. The study used an amniocentesis microarray cohort without structural ultrasound anomalies; this limitation is shown with the result.
- ACOG microarray guidance: Explains that microarray can detect submicroscopic copy-number changes beyond a standard karyotype and that diagnostic scope depends on the laboratory test ordered.
- Salomon et al. 2019: A meta-analysis used to explain why procedure-related loss estimates vary by study and can be lower when comparison pregnancies have similar baseline risks.
Method reviewed: 12 July 2026. This is educational context, not a recommendation for or against testing.