Here is a comprehensive summary of the newest NIPT/cfDNA guidelines:
NIPT/cfDNA Screening: Updated Guidelines (2025-2026)
Key Guideline Source
The most current guidance comes from SMFM Consult Series #74: "Cell-free DNA Screening for Aneuploidies: Updated Guidance" (Rink BD, Dugoff L, Kuller JA, 2025), formally endorsed by ACOG in November 2025. This document replaces the previous ACOG Practice Bulletin No. 226 (2020). The term "prenatal cfDNA screening" is now preferred over "NIPT."
Numbered Recommendations (with GRADE levels)
1. Common Trisomies - Universal Offer (GRADE 1B)
cfDNA screening for trisomies 21, 18, and 13 should be made routinely available to all obstetrical patients, regardless of age or baseline risk. It is the most sensitive and specific screening test for these conditions in any patient population. After pretest counseling, every patient has the right to pursue or decline.
- Performance: ~99% sensitivity for T21, ~96% for T18, ~91% for T13
- Available from 10 weeks gestation onward
- Remains a screening test - positive results require confirmation with CVS or amniocentesis
2. Sex Chromosome Aneuploidies - Opt-In Only (GRADE 1C)
Screening for sex chromosome aneuploidies (45,X; 47,XXX; 47,XXY; 47,XYY) should be available as an opt-in consideration with appropriate pretest counseling - not offered by default. Patients with a positive result for 45,X should be referred for posttest genetic counseling and diagnostic testing (consider maternal karyotype assessment).
3. Microdeletions - Not Recommended Routinely (GRADE 1C)
Routine general population screening for microdeletion conditions is NOT recommended. Patients specifically interested in 22q11.2 deletion screening may proceed only after counseling. For those seeking information on copy number variants broadly, diagnostic testing is preferred over cfDNA screening for microdeletion syndromes.
4. Genome-Wide Copy Number Variants - Not Recommended (GRADE 1C)
Routine cfDNA testing for large genome-wide copy number deletions or duplications is not recommended. Evidence for clinical utility remains insufficient.
5. Twin Gestations (GRADE 1B)
- cfDNA is recommended as a first-line screening option for T21 in twin gestations
- Detection rates for T18 and T13 in twins appear consistently high; cfDNA is recommended
- cfDNA for sex chromosome aneuploidies in twins is NOT recommended due to lack of data (GRADE 1C)
- cfDNA for higher-order multiples is NOT recommended (GRADE 1C)
6. Single-Gene Disorders - Not for Routine Use
cfDNA testing for single-gene disorders (e.g., de novo dominant or paternally inherited autosomal dominant conditions) is not recommended for routine use. Laboratories may offer it, but evidence on clinical utility and validity is insufficient, and complex counseling issues remain unresolved.
7. Rare Autosomal Trisomies (RATs)
Neither ACMG nor ISPD recommends routine cfDNA screening for RATs (trisomies other than 21, 18, 13) in unselected populations due to insufficient data.
Counseling Requirements (All Patients)
Pre-test counseling must cover:
- What the test screens for and its limitations
- Performance characteristics including positive predictive value (PPV) - which varies by population prevalence
- The distinction between screening and diagnosis
- Options to decline screening
- Post-test counseling is mandatory for any positive or non-reportable result
Positive results must be communicated clearly with the PPV, and patients should be referred to a provider with genetics expertise (genetic counselor, geneticist, or MFM specialist).
When cfDNA Should NOT Be Used (or Alternatives Preferred)
| Situation | Guidance |
|---|
| Vanishing twin syndrome | Serum screening preferred (demised twin placenta may shed aneuploid cfDNA, causing false positives) |
| Maternal organ transplant or stem cell therapy | cfDNA unreliable |
| Maternal mosaicism or translocation | cfDNA cannot capture these |
| Low fetal fraction | No-call result; may require repeat or alternative testing |
| Structural fetal anomalies on ultrasound | Offer diagnostic testing (CMA/karyotype), not cfDNA screening |
Fetal Fraction Considerations
- Inadequate fetal fraction (<4%) is a common cause of no-call results
- Associated with increased risk of adverse outcomes (per 2024 meta-analysis, PMID 39008086)
- Causes: obesity (most common), early gestational age, aneuploidy itself, low-molecular-weight heparin, ART
- A repeat test after 1-2 weeks is reasonable; persistent failure warrants genetic counseling
How This Differs From Previous ACOG 2020 Guidance
- More explicit opt-in framing for sex chromosome aneuploidies
- Stronger language against routine microdeletion and genome-wide CNV screening
- Clearer stance on twin gestations (cfDNA first-line for T21/T18/T13 in twins)
- Preferred terminology shifted from "NIPT" to "prenatal cfDNA screening"
- Single-gene disorder testing explicitly flagged as investigational only
Canadian Guideline (SOGC Guideline No. 456, 2024)
The Society of Obstetricians and Gynaecologists of Canada (SOGC) published an updated guideline in November 2024 (
PMID 39419445). Key points:
- cfDNA (NIPS) is the most accurate method for detecting major aneuploidies
- Availability in the public health system is not universal across Canada
- Shared decision-making and counseling are central
- Consistent with SMFM/ACOG on limitations of microdeletion screening
Bottom line: The 2025 SMFM/ACOG guidance strongly endorses universal availability of cfDNA for the three common trisomies, introduces stricter limits on sex chromosome and microdeletion add-ons, and is more explicit about when conventional serum screening remains the better alternative.