Lab Update No. 65: Non-Invasive Prenatal Testing: Confirmatory Testing Update
Dr Janin Alant – August 2025
Overview
Non-Invasive Prenatal Testing (NIPT) is a powerful screening tool that analyzes cell-free fetal DNA in maternal blood to detect:
- Trisomy 21 (Down syndrome)
- Trisomy 18
- Trisomy 13
- Sex chromosome abnormalities
Advantages:
- Non-invasive
- Available from 10 weeks’ gestation
- High sensitivity and specificity
- Reduces need for invasive procedures
Important: NIPT is a screening, not a diagnostic test. High-risk results must be confirmed via Chorionic Villus Sampling (CVS) or Amniocentesis.
Genetic Counselling
Comprehensive pre- and post-test counselling is essential to help patients understand:
- Test limitations
- Result implications
- Available choices
New Ampath Initiative
Ampath now offers free confirmatory testing and genetic counselling for high-risk NIPT results performed through Ampath.
Sample Types Accepted
- CVS or Amniotic Fluid (15–20 ml)
- Cord/postnatal blood (if invasive testing declined)
Process
- Contact: geneticsclinic@ampath.co.za
- Mnemonic used: CONNIPT