Summary & Overview
CPT 81421: Fetal Chromosomal Aneuploidy Genomic Sequence Analysis Panel
CPT code 81421 represents a genomic sequence analysis panel for detecting fetal chromosomal aneuploidy, including conditions such as trisomy 21 and monosomy X, using cell-free fetal DNA from maternal blood. This test is a cornerstone of modern prenatal screening, offering non-invasive, highly accurate detection of chromosomal abnormalities. The code requires analysis of chromosomes 13, 18, and 21, which are associated with the most common and clinically significant fetal aneuploidies.
Blue Cross Blue Shield is the primary payer covered in this analysis. Readers will gain insight into the clinical context of 81421, including its role in prenatal care, typical laboratory site of service, and its relationship to other genetic testing codes. The publication also covers relevant policy updates, coding benchmarks, and the importance of this test in national prenatal screening practices. The summary provides a comprehensive overview for healthcare professionals, laboratory administrators, and policy stakeholders seeking to understand the utilization and coverage landscape for fetal chromosomal aneuploidy testing.
CPT Code Overview
CPT code 81421 is used for genomic sequence analysis panels that detect fetal chromosomal aneuploidy, such as trisomy 21 and monosomy X, through circulating cell-free fetal DNA in maternal blood. This test must include analysis of chromosomes 13, 18, and 21. The service type is genetic testing, and it is typically performed in a laboratory setting (Place of Service 81). This code is central to prenatal screening protocols, providing critical information for early detection of chromosomal abnormalities during pregnancy.
Clinical & Coding Specifications
Clinical Context
A pregnant patient presents for routine prenatal care and is offered non-invasive prenatal testing (NIPT) to screen for common fetal chromosomal aneuploidies, such as trisomy 21 (Down syndrome), trisomy 18, and trisomy 13. The test involves collecting a blood sample from the mother, which is sent to a laboratory for genomic sequence analysis of circulating cell-free fetal DNA. The ordering provider may be an obstetrician, genetic counselor, or medical geneticist. The laboratory performs the analysis and reports results to the provider, who discusses findings with the patient as part of antenatal screening and pregnancy supervision, especially in cases of high-risk pregnancies or suspected chromosomal abnormalities.
Coding Specifications
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Modifiers:
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26: Used to indicate the professional component of the service, typically when the interpretation of the test is performed by a physician or qualified healthcare professional. - Modifier
TC: Used to indicate the technical component, which covers the laboratory processing and analysis of the specimen.
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Provider Taxonomies:
Taxonomy Code Specialty Name 207SG0201XGenetic Counselor, MS 207SG0202XMedical Geneticist 207VG0400XObstetrics & Gynecology Physician
These specialties are commonly involved in ordering, interpreting, or counseling for fetal chromosomal aneuploidy testing.
Related Diagnoses
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Z36.0: Encounter for antenatal screening for chromosomal anomalies- Used when the patient is undergoing routine screening for fetal chromosomal abnormalities.
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O35.1XX0: Maternal care for (suspected) chromosomal abnormality in fetus, not applicable or unspecified- Applied when there is suspicion or concern for chromosomal abnormality in the fetus during pregnancy.
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Z34.90: Encounter for supervision of normal pregnancy, unspecified, unspecified trimester- Used for routine prenatal care in a normal pregnancy, where screening may still be performed.
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O09.90: Supervision of high-risk pregnancy, unspecified, unspecified trimester- Indicates the patient is considered high-risk, which may prompt more frequent or specialized screening.
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Z36.89: Encounter for other antenatal screening- Used for antenatal screening procedures not specified elsewhere, including additional genetic tests.
Related CPT Codes
| CPT Code | Description | Clinical Relationship |
|---|---|---|
81420 | Fetal chromosomal aneuploidy genomic sequence analysis panel | Similar to 81421, may be used for broader or alternative panels |
81507 | Fetal aneuploidy DNA sequence analysis | Alternative method for fetal aneuploidy screening |
81228 | Cytogenomic constitutional (genome-wide) microarray analysis | Used for broader genomic analysis, sometimes in follow-up |
81229 | Cytogenomic constitutional (genome-wide) microarray analysis; each additional microarray | Used when additional microarray analysis is required |
Codes 81420 and 81507 are commonly used as alternatives or complements to 81421 in fetal aneuploidy screening workflows. Codes 81228 and 81229 may be used for more comprehensive genomic analysis, often in cases where initial screening indicates abnormalities.
National Reimbursement Benchmarks
Nationally, Blue Cross Blue Shield and BUCA (average commercial) both reimburse CPT code 81421 at a mean rate of $80.02. Medicare rates are not available in the input for comparison.
Rate dispersion for both Blue Cross Blue Shield and BUCA is minimal, with the 25th, 50th, and 75th percentiles all at $80.00. This indicates a very tight range, with no significant variation in rates across these payers.
The table and chart below present the full breakdown of national mean rates and percentile values for each payer.
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