NIPT - Non-Invasive Prenatal Testing (Cell-Free DNA)
Blood test analyzing fetal DNA to screen for chromosomal conditions like Down syndrome with high accuracy.
📅 When Performed
Week 10 or later
⏱️ Results Timeline
1-2 weeks
Overview
Non-invasive prenatal testing (NIPT), also called cell-free DNA testing, analyzes tiny fragments of fetal DNA circulating in your blood to screen for chromosomal conditions. It's highly accurate for detecting Down syndrome (trisomy 21), Edwards syndrome (trisomy 18), and Patau syndrome (trisomy 13).
This test can be done as early as 10 weeks and only requires a simple blood draw from your arm. It's "non-invasive" meaning there's no risk to the baby, unlike diagnostic tests like amniocentesis.
NIPT can also reveal your baby's sex very early in pregnancy. While it's a screening test (not diagnostic), it's much more accurate than older screening methods and has largely replaced them for many women.
🎯 Purpose of Test
- •Screen for Down syndrome (trisomy 21) with 99% accuracy
- •Screen for Edwards syndrome (trisomy 18) and Patau syndrome (trisomy 13)
- •Detect some sex chromosome abnormalities
- •Determine baby's sex (optional)
- •Provide reassurance or identify need for diagnostic testing
- •Risk-free screening available early in pregnancy
🔬 How It's Performed
- 1.Simple blood draw from your arm
- 2.Can be done after 10 weeks of pregnancy
- 3.Blood contains small fragments of placental DNA
- 4.Lab analyzes DNA for chromosomal abnormalities
- 5.Takes 1-2 weeks for results
- 6.Some tests also check for microdeletions
- 7.Sex can be determined from Y chromosome presence
👀 What to Expect
- →Quick blood draw, just like any blood test
- →No risks to pregnancy
- →Results in 1-2 weeks (sometimes up to 10 days)
- →High-risk results warrant follow-up with genetic counselor
- →May need diagnostic test (amnio) to confirm positive result
- →Low-risk result is very reassuring
- →Occasionally test needs to be redrawn (low fetal fraction)
✓ Normal Results
Low risk for all conditions tested - very reassuring, no further testing needed
⚠️ Abnormal Results
- •High risk result means increased chance of condition
- •NOT a diagnosis - screening test only
- •Positive result should be confirmed with amniocentesis or CVS
- •False positives possible (rare but occur)
- •Meet with genetic counselor to discuss results
- •Decide if diagnostic testing desired
- •High-risk result is stressful but not definitive
⚠️ Risks & Considerations
- •No physical risks - just a blood draw
- •Small risk of inconclusive result (need redraw)
- •Psychological stress if high-risk result
- •Rare false positive or false negative
- •May reveal incidental findings (like maternal chromosomal condition)
- •Not covered by all insurance, can be expensive
📝 How to Prepare
- →No fasting or special preparation required
- →Must be at least 10 weeks pregnant
- →Discuss with provider if appropriate for your situation
- →Understand it's screening, not diagnostic
- →Decide if you want to know sex
- →Check if insurance covers test (expensive without coverage)
- →Be prepared for waiting period for results