Currentsierra health and lifePolicy 2026T0559FF

Chromosome Microarray Testing (Non-Oncology Conditions)

Policy governing coverage and medical necessity of chromosome microarray testing (aCGH and SNP array) for non-oncology indications under UnitedHealthcare Commercial and Individual Exchange plans; affects ordering providers and laboratories performing constitutional chromosomal analysis.

Policy Summary

Payersierra health and life

PolicyChromosome Microarray Testing (Non-Oncology Conditions)

Policy CodePolicy 2026T0559FF

Change TypeTemplate Update

Effective DateJan 1, 2026

Next Review Date

Key ActionObtain and document face-to-face genetic counseling and informed consent prior to ordering chromosome microarray testing.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

aCGH/SNPProven technologies

7 codesProcedure codes listed

Commercial/ExchangeApplies to

yesPrenatal/fetal covered

NCApplicable states

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Coverage Criteria

inv-01: Medically necessary indications

Covered when ALL of the following are met (documented indications):

Prenatal and fetal evaluations: Chromosome microarray testing using aCGH and/or SNP array is medically necessary for evaluation of an embryo/fetus in cases of intrauterine fetal demise or stillbirth; testing products of conception following pregnancy loss; and for individuals undergoing invasive prenatal diagnostic testing (amniocentesis, chorionic villus sampling, or fetal tissue sampling).

Coverage Rationale: CMA is proven and medically necessary for these prenatal/fetal evaluations.

Pediatric developmental and neurologic indications: Evaluation of individuals with one or more of the following: autism spectrum disorder (ASD); isolated severe congenital heart disease; multiple anomalies not specific to a well-delineated genetic syndrome; or developmental delay/intellectual disability when a specific syndrome is not suspected.

Medicare Advantage Policy lists these as covered indications.

inv-02: General first-tier recommendation (ACMG)

Covered when consistent with professional guidelines and clinical indications described below

ACMG first-tier recommendation: Chromosomal microarray analysis (CMA) is recommended as the first-tier test in the evaluation of individuals with neurodevelopmental disability and congenital anomalies.

ACMG practice report: CMA first-tier; notes CMA may not detect balanced rearrangements or UPD and additional testing may be needed.

inv-03: Prenatal and obstetric indications

Prenatal/Obstetric indications with evidence of diagnostic yield

Fetal structural anomalies or multiple anomalies: CMA is considered first-tier and is recommended for fetuses with structural anomalies, particularly non-isolated or multiple structural anomalies, due to increased diagnostic yield compared with karyotype alone.

Systematic reviews/meta-analyses report higher CMA yields for multiple structural anomalies (see Mastromoro et al.).

Congenital heart defects (CHD): CMA is recommended for fetuses with congenital heart defects, especially non-isolated CHD; consider CMA when conventional karyotype/FISH is normal to detect submicroscopic CNVs.

Meta-analyses report higher proportions of chromosome abnormalities in non-isolated CHD vs isolated CHD.

Increased nuchal translucency (NT): CMA provides incremental diagnostic yield in fetuses with increased nuchal translucency; higher NT measurements are associated with greater CMA yield (e.g., NT >= 3.5 mm noted for substantial yield).NT >= 2.5 mm considered in analyses; NT >= 3.5 mm associated with substantial yield

inv-04: Limitations and follow-up testing

Test limitations and follow-up

Limitations requiring follow-up: CMA may detect variants of uncertain significance and false positives that require further evaluation; CMA cannot reliably detect balanced chromosomal rearrangements or all forms of uniparental disomy (UPD); additional testing (e.g., karyotype, FISH, parental studies, or sequencing) may be needed to clarify findings and inform counseling.

Policy notes use of genomic databases for interpretation and recommends follow-up cytogenetic/FISH and parental testing when CNV significance is uncertain.

inv-05: Medically Necessary / Covered Criteria

Covered when clinical indications meet guideline recommendations

Prenatal with structural anomalies: When one or more major fetal structural abnormalities are identified on ultrasound and invasive diagnostic testing is being performed, CMA is the recommended diagnostic test and can replace conventional fetal karyotype.

ACOG/SMFM: CMA primary test for structural abnormalities; ACMG and other societies concur.

Prenatal other indications: CMA may be used for confirmatory diagnosis after abnormal NIPS, as reflex testing when small CNVs are reported by NIPS, for evaluation of stillbirth/intrauterine fetal demise, and when NIPS sex determination is discordant with physical findings suggesting disorder of sexual differentiation.

ACMG practice resource and ACOG/SMFM guidance support these uses of CMA.

Pediatric neurodevelopmental indications: CMA is recommended as a first-tier test for individuals with neurodevelopmental disability, congenital anomalies, unexplained developmental delay/intellectual disability, or autism spectrum disorder when a specific syndrome is not identified, often replacing karyotype and FISH as initial cytogenetic testing.

inv-06: Covered indications and prerequisites

Covered when recommendations from professional societies are met (examples below):

Indications supporting CMA: CMA is indicated as a first-line test for individuals with developmental delay/intellectual disability (DD/ID/GDD), autism spectrum disorder (ASD), or multiple congenital anomalies not specific to a well-delineated genetic syndrome.

Supported by ACMG, ISCA, CCMG, AACAP guidance as first-tier testing.

Prenatal indications: When major fetal structural abnormalities are identified on ultrasound and invasive prenatal diagnostic testing is planned, CMA is the recommended diagnostic test; CMA is also recommended for evaluation after intrauterine fetal demise or stillbirth when a genetic evaluation is pursued.

ACMG technical standard and ACOG/SMFM practice bulletins recommend CMA in these prenatal contexts.

Prior targeted testing: If clinical presentation or family history suggests a recognizable genetic syndrome, perform syndrome-specific targeted testing (e.g., Fragile X) first; if that testing is negative, CMA is indicated as the next step.

AACAP and AAN recommend targeted testing when indicated prior to CMA.

Chromosome microarray testing using array comparative genomic hybridization (aCGH) or single-nucleotide polymorphism (SNP) array is not considered medically necessary for populations and clinical conditions that are not specifically listed in the policy's covered indications. This reflects the Medicare Advantage statement that such uses are unproven and lack sufficient evidence of efficacy.

The extracted applicable code listings enumerate diagnosis codes to support testing but do not include explicit exclusion rules or a separate list of tests/indications that are expressly excluded; providers should rely on the covered indications and clinical criteria rather than assuming additional exclusions are present in this excerpt.

An intrinsic limitation of chromosomal microarray analysis is that it cannot reliably detect balanced chromosomal rearrangements (for example, reciprocal translocations or inversions) where there is no net gain or loss of chromosomal material; when detection of a balanced rearrangement is required, CMA is therefore not an appropriate sole diagnostic test and follow-up cytogenetic/karyotype analysis should be considered.

Chromosomal microarray analysis would not be considered medically necessary when a clinical diagnosis of a disorder or syndrome is readily apparent from the history and physical examination alone, because the test is unlikely to change management in such cases.

The policy identifies circumstances in which microarray testing is considered investigational or of limited value, including when appropriate informed consent is absent or when patients/guardians lack adequate understanding of the potential implications and required follow‑up for test results; under these circumstances testing may be deemed investigational.

Use of chromosomal microarray testing outside the indications listed in the coverage rationale is considered not medically necessary or unproven and may be denied when submitted for populations or conditions not enumerated as covered.

In the source excerpts provided there are no explicit standalone statements labeling additional specific tests or indications as 'not medically necessary'; the document instead focuses on listing applicable diagnosis codes and describing covered clinical scenarios.

The reviewed document chunks do not contain additional explicit 'not medically necessary' declarations; limitations and appropriate follow-up testing are described, but explicit negative coverage lists are not present in these sections.

The AAN model coverage language included in the policy notes that testing may be considered investigational when there is absence of appropriate informed consent or when there is inadequate knowledge about the implications of test results and actions required to address them; such situations limit the clinical value of CMA.

Consistent with the AAN model coverage policy, chromosomal microarray analysis is not considered medically necessary when a disorder or syndrome diagnosis is readily apparent from clinical evaluation alone, because the test would not be expected to alter management.

Covered Indications

inv-61: Evaluation for intrauterine fetal demise/stillbirth, products of conception after pregnancy loss, invasive prenatal testing (amniocentesis/CVS/fetal tissue sampling).

Evaluation for intrauterine fetal demise/stillbirth, products of conception after pregnancy loss, invasive prenatal testing (amniocentesis/CVS/fetal tissue sampling).

POC / stillbirth testing: CMA of products of conception or fetal tissue is medically necessary to evaluate intrauterine fetal demise or stillbirth when cytogenetic analysis is desired, due to its increased likelihood of obtaining results and improved detection of causative abnormalities compared with conventional karyotype.

Coverage Rationale and ACOG/SMFM recommend CMA for evaluation of POC and stillbirth.

Invasive prenatal diagnostic testing: When invasive prenatal diagnostic testing (amniocentesis or CVS) is performed for clinical indications, CMA should be available and is recommended as the primary test for fetuses with structural abnormalities; either CMA or karyotype may be performed for structurally normal fetuses undergoing invasive testing per professional guidance.

ACOG/SMFM: CMA should be available to any patient undergoing invasive diagnostic testing and is primary for structural anomalies.

Coding

Procedure/CPT/HCPCS codesmixed

0156U	Copy number (e.g., intellectual disability, dysmorphology), sequence analysis.
0209U	Cytogenomic constitutional (genome-wide) analysis, interrogation of genomic regions for copy number, structural changes and areas of homozygosity for chromosomal abnormalities
81228	Cytogenomic (genome-wide) analysis for constitutional chromosomal abnormalities; interrogation of genomic regions for copy number variants, comparative genomic hybridization [CGH] microarray analysis.
81229	Cytogenomic (genome-wide) analysis for constitutional chromosomal abnormalities; interrogation of genomic regions for copy number and single nucleotide polymorphism (SNP) variants, comparative genomic hybridization (CGH) microarray analysis.
81349	Cytogenomic (genome-wide) analysis for constitutional chromosomal abnormalities; interrogation of genomic regions for copy number and loss-of-heterozygosity variants, low-pass sequencing analysis.
81479	Unlisted molecular pathology procedure
S3870	Comparative genomic hybridization (CGH) microarray testing for developmental delay, autism spectrum disorder and/or intellectual disability

Diagnosis (ICD-10) codes (partial list)ICD-10

F70	Mild intellectual disabilities.
F71	Moderate intellectual disabilities.
F72	Severe intellectual disabilities.
F73	Profound intellectual disabilities.
F78.A1	SYNGAP1-related intellectual disability.
F78.A9	Other genetic related intellectual disability.
F79	Unspecified intellectual disabilities.
F80.0	Phonological disorder.
F84.0	Autistic disorder.
H93.25	Central auditory processing disorder.

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Applicable ICD-10 O35 series (maternal care for suspected fetal conditions)ICD-10

O35.07X0	Maternal care for (suspected) central nervous system malformation or damage in fetus, microcephaly, not applicable or unspecified.
O35.07X1	Maternal care for (suspected) central nervous system malformation or damage in fetus, microcephaly, fetus 1.
O35.07X2	Maternal care for (suspected) central nervous system malformation or damage in fetus, microcephaly, fetus 2.
O35.07X3	Maternal care for (suspected) central nervous system malformation or damage in fetus, microcephaly, fetus 3.
O35.07X4	Maternal care for (suspected) central nervous system malformation or damage in fetus, microcephaly, fetus 4.
O35.07X5	Maternal care for (suspected) central nervous system malformation or damage in fetus, microcephaly, fetus 5.
O35.07X9	Maternal care for (suspected) central nervous system malformation or damage in fetus, microcephaly, other fetus.
O35.08X0	Maternal care for (suspected) central nervous system malformation or damage in fetus, spina bifida, not applicable or unspecified.
O35.08X1	Maternal care for (suspected) central nervous system malformation or damage in fetus, spina bifida, fetus 1.
O35.08X2	Maternal care for (suspected) central nervous system malformation or damage in fetus, spina bifida, fetus 2.

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Applicable ICD-10 O35 series — specific chromosomal abnormalitiesICD-10

O35.11X0	Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, not applicable or unspecified.
O35.11X1	Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, fetus 1.
O35.12X0	Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 18, not applicable or unspecified.
O35.13X0	Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 21, not applicable or unspecified.
O35.14X0	Maternal care for (suspected) chromosomal abnormality in fetus, Turner Syndrome, not applicable or unspecified.
O35.15X0	Maternal care for (suspected) chromosomal abnormality in fetus, sex chromosome abnormality, not applicable or unspecified.
O35.19X0	Maternal care for (suspected) chromosomal abnormality in fetus, other chromosomal abnormality, not applicable or unspecified.

Applicable ICD-10 O35 other/organ-specific fetal anomaly codesICD-10

O35.2XX0	Maternal care for (suspected) hereditary disease in fetus, not applicable or unspecified.
O35.8XX0	Maternal care for other (suspected) fetal abnormality and damage, not applicable or unspecified.
O35.AXX0	Maternal care for other (suspected) fetal abnormality and damage, fetal facial anomalies, not applicable or unspecified.
O35.BXX0	Maternal care for other (suspected) fetal abnormality and damage, fetal cardiac anomalies, not applicable or unspecified.
O35.CXX0	Maternal care for other (suspected) fetal abnormality and damage, fetal pulmonary anomalies, not applicable or unspecified.
O35.DXX0	Maternal care for other (suspected) fetal abnormality and damage, fetal gastrointestinal anomalies, not applicable or unspecified.
O35.EXX0	Maternal care for other (suspected) fetal abnormality and damage, fetal genitourinary anomalies, not applicable or unspecified.
O35.FXX0	Maternal care for other (suspected) fetal abnormality and damage, fetal musculoskeletal anomalies of trunk, not applicable or unspecified.
O35.GXX0	Maternal care for other (suspected) fetal abnormality and damage, fetal upper extremities anomalies, not applicable or unspecified.
O35.HXX0	Maternal care for other (suspected) fetal abnormality and damage, fetal lower extremities anomalies, not applicable or unspecified.

Perinatal/newborn outcome and specialized codesICD-10

P02.9	Newborn affected by abnormality of membranes, unspecified.
P95	Stillbirth.
QA0.0159	Neurodevelopmental disorder, related to other genes associated with transcription and gene expression.

Congenital cardiac, syndromic, and chromosomal ICD-10 codesICD-10

Q20.1	Double outlet right ventricle.
Q21.0	Ventricular septal defect.
Q21.3	Tetralogy of Fallot.
Q22.5	Ebstein's anomaly.
Q23.4	Hypoplastic left heart syndrome.
Q87.86	Kleefstra syndrome.
Q90.0	Trisomy 21, nonmosaicism (meiotic nondisjunction).
Q90.1	Trisomy 21, mosaicism (mitotic nondisjunction).
Q91.0	Trisomy 18, nonmosaicism (meiotic nondisjunction).
Q91.4	Trisomy 13, nonmosaicism (meiotic nondisjunction).

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Antenatal screening, birth outcome, and history codesICD-10

Z36.0	Encounter for antenatal screening for chromosomal anomalies.
Z37.1	Single stillbirth.
Z37.3	Twins, one liveborn and one stillborn.
Z37.4	Twins, both stillborn.
Z37.60	Multiple births, unspecified, some liveborn.
Z87.74	Personal history of (corrected) congenital malformations of heart and circulatory system.

Applicable diagnosis codesICD-10

Q93.0	Whole chromosome monosomy, nonmosaicism (meiotic nondisjunction).
Q93.1	Whole chromosome monosomy, mosaicism (mitotic nondisjunction).
Q93.2	Chromosome replaced with ring, dicentric or isochromosome.
Q93.3	Deletion of short arm of chromosome 4.
Q93.4	Deletion of short arm of chromosome 5.
Q93.7	Deletions with other complex rearrangements.
Q93.51	Angelman syndrome.
Q93.52	Phelan-McDermid syndrome.
Q93.59	Other deletions of part of a chromosome.
Q93.81	Velo-cardio-facial syndrome.

1–10 of 38

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Covered CPT Codesmixed

No codes listed

Numeric threshold summary

Numeric thresholds presentNone — no numeric thresholds are specified in this excerpt.

Context noteThresholds for tests and indications are described qualitatively elsewhere (e.g., NT cutoffs), but this excerpt contains no numeric threshold values.

Implication for coding/authorizationDo not rely on numeric cutoffs from this excerpt for prior authorization decisions; use the specific guideline sections or documented numeric thresholds when needed.

Nuchal translucency (NT) and CMA yield

Provider Actions and Operational Requirements

Billing Rule

Diagnosis codes to support authorization

Diagnosis codes to support authorization: Use applicable ICD-10-CM maternal care, fetal outcome, newborn outcome, and neurodevelopmental disorder codes to support medical necessity when submitting authorization requests or claims. Examples include maternal care for suspected fetal anomalies (O35 series), intrauterine death (O36.4XX), newborn affected by abnormality of membranes (P02.9), stillbirth (P95), and developmental/neurogenetic disorder codes where relevant. Listing of a diagnosis code in this policy does not guarantee coverage; verify member benefits and plan-specific requirements.

Example maternal/fetal ICD-10 codes: O35.xxx series (maternal care for suspected fetal anomaly)
Outcome/maternal care codes: P02.9 (newborn affected by abnormality of membranes), P95 (stillbirth), O36.4XX (intrauterine death)
Use appropriate neurodevelopmental disorder/clinical codes to support testing for DD/ID/ASD

Not Covered / Investigational

Uses of CMA that fall outside the specifically listed and evidence-supported indications (for example, to evaluate populations or conditions not enumerated in the coverage rationale) are described as unproven and not medically necessary and therefore are not covered.

Within the provided 'Not Covered' excerpts there are no additional explicit listings of specific tests or clinical indications that are categorically not covered; instead the document emphasizes supported diagnosis codes and covered clinical contexts.

Because chromosomal microarray testing detects copy number variants and cannot detect structural changes that do not alter copy number, CMA is not appropriate as the sole test when the clinical question specifically requires detection of balanced chromosomal rearrangements; conventional cytogenetic/karyotype analysis is required in those circumstances.

Evidence does not support routine use of CMA as the first-line test for all individuals with epilepsy; meta-analysis data cited in the policy report a relatively low diagnostic yield for CMA in epilepsy (~9%), and professional guidance calls for more targeted evaluation based on phenotype and comorbidities.

The policy indicates CMA use without documented informed consent, when test implications are not understood by the patient/guardian, or when a clinical diagnosis is already evident, is not covered because these situations limit the test's clinical value and may render results uninterpretable or unactionable.

Definitions and Background

Chromosomal microarray testing (aCGH and SNP array) interrogates the genome for copy number variants and regions of homozygosity. It can be performed as targeted or genome-wide analyses and detects deletions and duplications across the genome; results may be classified as pathogenic, benign, or variants of uncertain significance and may require parental studies, cytogenetics, or other follow-up testing to clarify significance.

Developmental Delay

DefinitionDevelopmental Delay: describes children younger than 5 years who present with delays in attainment of developmental milestones at the expected age.

Age boundaryTypically used for children younger than 5 years of age.

Clinical useApplied when assessing early childhood delays to determine need for genetic evaluation including CMA when no specific syndrome is suspected.

Intellectual Disability

Definition

Eligibility Requirements

No top-level eligibility requirement nodes are specified in the extracted sections of the policy.

Policy Summary

Payersierra health and life

PolicyChromosome Microarray Testing (Non-Oncology Conditions)

Policy CodePolicy 2026T0559FF

Change TypeTemplate Update

Effective DateJan 1, 2026

Next Review Date

Key ActionObtain and document face-to-face genetic counseling and informed consent prior to ordering chromosome microarray testing.

SourceLink

On This Page

Authors recommend considering increased NT as an indication for CMA alongside other malformations.

Fetal growth restriction (FGR) with anomalies: CMA may be useful in fetuses with growth restriction when structural malformations are present because studies report higher detection rates of pathogenic CNVs in these contexts.

SMFM/other studies support offering CMA when FGR is accompanied by malformations or in unexplained isolated FGR <32 weeks.

Products of conception / pregnancy loss: CMA has a higher informative yield compared with conventional karyotype for products of conception (POC) and early pregnancy loss and can detect clinically significant chromosomal abnormalities and pathogenic CNVs in POC samples.

Meta-analyses report pooled diagnostic yields (e.g., chromosomal abnormalities ~49.9% in POC studies; pCNV detection also reported).

ACMG, AACAP, ISCA, CCMG and related professional guidance designate CMA as first-line in these indications.

When targeted testing preferred first: If a specific recognizable genetic syndrome is suspected (e.g., Fragile X, PTEN, Rett, tuberous sclerosis, Prader-Willi, Angelman, Down), perform syndrome-specific targeted testing first; if negative or unrevealing, proceed to CMA (and Fragile X testing as indicated).

AACAP and other specialty guidelines recommend syndrome-directed testing prior to CMA when indicated by phenotype or family history.

Testing value limitations and prerequisites: Testing should be accompanied by appropriate pretest face-to-face genetic counseling and informed consent; lack of informed consent, inadequate understanding of test implications, or when a clinical diagnosis is already apparent may render CMA investigational or not medically necessary.

AAN model coverage policy and ACOG/SMFM emphasize counseling, consent, and documentation; parental testing and follow-up are recommended for VUS.

Counseling and consent: Face-to-face genetic counseling by an appropriately trained professional and documentation of informed consent (parental consent and patient assent as applicable) should be provided before testing; parental testing and follow-up plans should be documented for variants of uncertain significance.

AAN and ACOG/SMFM guidance require counseling and informed consent prior to CMA.

inv-62: Evaluation for autism spectrum disorder, isolated severe congenital heart disease, multiple anomalies not specific to well-delineated syndrome, and developmental delay/ID when specific syndrome not suspected.

Autism spectrum disorder and related: CMA is indicated for evaluation of individuals with autism spectrum disorder (ASD), particularly when no specific syndromic diagnosis is identified, as CMA is a first-tier diagnostic test for ASD per ACMG/ACMG-associated guidance.

Medicare Advantage Policy and ACMG/ACMG resources list ASD as an indication; AACAP reports abnormal CMA rates in ASD cohorts.

Isolated severe congenital heart disease and multiple anomalies: CMA is indicated for individuals with isolated severe congenital heart disease and for those with multiple anomalies not specific to a well-delineated genetic syndrome, due to the increased likelihood of identifying clinically significant CNVs.

Medicare Advantage Policy and ACMG technical standards support CMA in congenital anomalies and CHD contexts.

Developmental delay / intellectual disability when no specific syndrome suspected: CMA is indicated as a first-tier test for individuals with developmental delay or intellectual disability when a specific recognizable genetic syndrome is not suspected.

ACMG practice resources and ISCA/ACMG guidance designate CMA as first-line for DD/ID.

inv-63: Suspected fetal chromosomal abnormality (e.g., Trisomy 13/18/21), congenital anomalies, or recognized syndromes listed in Q-series codes.

Suspected fetal chromosomal abnormality: CMA is appropriate when there is suspicion of fetal chromosomal abnormality (e.g., Trisomy 13, 18, 21) or other congenital chromosomal syndromes (Q-series codes) identified by ultrasound or clinical evaluation, and for maternal care situations coded within the O35.* series.

Applicable O35 and Q-series codes are listed as supporting diagnoses for maternal care for suspected fetal conditions.

Recognized syndromes and anomalies: When ultrasound or clinical findings suggest recognized syndromes or congenital anomalies, CMA can be used to detect CNVs associated with these conditions as part of the diagnostic evaluation.

CMA detects submicroscopic CNVs and has higher diagnostic yield in many fetal anomaly contexts per systematic reviews.

inv-64: Evaluation of individuals with neurodevelopmental disability and congenital anomalies (first-tier); prenatal evaluation of fetuses with structural anomalies, non-isolated findings, CHD, increased NT, FGR with anomalies, stillbirth, or abnormal NIPS results.

First-tier for neurodevelopmental disability and congenital anomalies: CMA is recommended as a first-tier test for individuals with neurodevelopmental disability and congenital anomalies; prenatal evaluation of fetuses with structural anomalies (including non-isolated findings, CHD, increased NT, and FGR with anomalies) and evaluation of stillbirth are supported indications for CMA.

ACMG and ACOG/SMFM guidelines recommend CMA as first-line in these settings; systematic reviews/meta-analyses report diagnostic yields supporting this approach.

Abnormal NIPS or discordant sex results: CMA may be used for confirmatory diagnosis after abnormal noninvasive prenatal screening (NIPS) results, as a reflex to normal karyotype when small CNVs are reported by NIPS, or when NIPS sex determination is discordant with physical findings.

ACMG practice resource recommends CMA on CVS or amniocentesis for confirmatory diagnosis of abnormal NIPS and for follow-up of small CNVs reported by NIPS.

inv-65: Neurodevelopmental disability, congenital anomalies, unexplained developmental delay/ID, ASD when no specific syndrome identified, prenatal structural fetal abnormalities, stillbirth evaluation, confirmatory testing after abnormal NIPS or discordant sex results.

Neurodevelopmental and congenital anomaly indications: CMA is medically necessary for evaluation of neurodevelopmental disability, congenital anomalies, unexplained developmental delay/intellectual disability, and autism spectrum disorder when no specific syndrome is identified; it is also indicated for prenatal structural fetal abnormalities, stillbirth evaluation, and as confirmatory testing after abnormal NIPS or discordant sex results.

Multiple specialty guidelines (ACMG, ACOG/SMFM, SMFM, AACAP) support these indications and report yields for abnormal CMA in these populations.

Confirmatory and reflex testing: Use CMA to confirm abnormal NIPS findings, to follow up small CNVs reported on screening, or to investigate discordant fetal sex results when indicated by clinical findings.

ACMG practice resources outline CMA use for NIPS follow-up and confirmatory testing.

inv-66: Evaluation of multiple congenital anomalies, apparently non-syndromic developmental delay/ID, and ASD; recommended first-tier in prenatal major structural abnormalities and stillbirth evaluation.

Multiple congenital anomalies and non-syndromic DD/ID/ASD: CMA is recommended as a first-tier test for individuals with multiple congenital anomalies, apparently non-syndromic developmental delay/intellectual disability, and autism spectrum disorder.

ACMG technical standard, ISCA consortium, and ACMG revision endorse CMA as first-tier for these indications.

Prenatal major structural abnormalities and stillbirth evaluation: CMA is recommended as the diagnostic test in prenatal cases with major fetal structural abnormalities undergoing invasive testing and for evaluation of stillbirth when genetic diagnosis is pursued.

ACMG and ACOG/SMFM guidance indicate CMA can replace karyotype in these prenatal contexts.

Actionable NT cutoff

Nuchal translucency (NT) ≥ 3.5 mm: associated with a substantial incremental diagnostic yield for CMA.

Lower NT thresholds reportedIncremental CMA detection rates were reported for isolated NT ≥2.5 mm (2.35% incremental yield) and NT ≥3.0 mm (3.89% incremental yield).

Relative findingsKaryotype abnormalities were the most frequent across NT strata, but CMA provided additional (incremental) diagnostic findings, especially at higher NT measurements.

Prior Authorization

Prior authorization / counseling

Prior authorization / counseling: Prior authorization requirements depend on the member's benefit plan. Genetic counseling is strongly recommended and—where required by guideline or plan—must be documented prior to ordering CMA. For prenatal diagnostic CMA, ensure invasive specimen collection (amniocentesis or CVS) is planned and documented. Obtain informed consent that addresses potential variants of uncertain significance, non-paternity, consanguinity, and adult-onset findings.

Check member-specific prior authorization rules before ordering
Document face-to-face pre-test genetic counseling when required
Document informed consent for prenatal CMA including discussion of VUS, non-paternity, and implications

Note

Indication-based availability for prenatal invasive testing

Indication-based availability for prenatal invasive testing: CMA should be available to patients undergoing invasive prenatal diagnostic testing. CMA is recommended as the primary test (can replace karyotype) for fetuses with one or more major structural anomalies identified by ultrasound and is recommended for evaluation of stillbirth or when karyotype is unobtainable.

Offer CMA to any patient undergoing invasive prenatal diagnostic testing
Prefer CMA as first-line for fetal structural anomalies detected by ultrasound
Use CMA for evaluation of stillbirths and some cases where karyotype cannot be obtained

Documentation Required

Verify member benefits before authorization

Verify member benefits before authorization: Benefit coverage is determined by the member-specific benefit plan document and applicable laws or mandates. Medical record documentation may be required to demonstrate that the member meets clinical criteria for coverage but does not guarantee payment.

Confirm coverage and prior authorization requirements with the member's plan before ordering
Provide medical records and documentation to support the indicated diagnosis and testing rationale

Billing Rule

Billing risk from incorrect diagnosis coding

Billing risk from incorrect diagnosis coding: Use accurate and specific diagnosis codes that reflect the clinical indication for testing. Absence of appropriate supporting diagnosis codes or documentation may result in claim denial or payment delay.

Avoid generic or nonspecific diagnosis coding when a specific maternal/fetal or neurodevelopmental diagnosis is available
Include maternal/fetal outcome codes (e.g., O35 series, P02.9, P95) when applicable to prenatal or stillbirth testing

Note

Provider action: None explicit

None explicit in this section: No additional ordering provider type restrictions or step-therapy requirements are specified within this section of the policy beyond following professional guidelines and member benefit rules.

Follow specialty guidance and plan-specific prior authorization processes
No explicit provider-type or step therapy mandates stated here

Denial Risk

Consent and clinical value limits

Consent and clinical value limits: Obtain appropriate informed consent prior to testing. Testing may be considered of limited value or investigational when there is inadequate informed consent, lack of understanding about test implications/actions, when a clinical diagnosis is already evident, or for indications not delineated by guidelines.

Document informed consent or parental consent and patient assent when applicable
Testing may be not medically necessary when diagnosis is clinically apparent without need for CMA
Lack of informed consent or inadequate counseling are grounds to consider testing not medically necessary

Denial Risk

Situations limiting value / denial triggers

Situations limiting value / denial triggers: CMA is considered investigational or not medically necessary for populations and indications not specified by guidelines. Denial risk increases when documentation of clinical indications, counseling, or informed consent is insufficient, or when targeted syndrome testing would be expected to yield diagnosis.

CMA using aCGH or SNP array is unproven and not medically necessary for populations/conditions not listed in guideline indications
Absence of documented counseling, consent, or clinical rationale may lead to denial
If a specific syndrome is clinically suspected, targeted testing should be done first (see sequencing guidance) and CMA may be denied if targeted testing has not been attempted when indicated

Billing Rule

Use of outcome and maternal care ICD-10 codes

Use of outcome and maternal care ICD-10 codes: When applicable, include maternal care (O35 series), fetal outcome, intrauterine death (O36.4XX), newborn outcome (P02.9), and stillbirth (P95) codes to support prenatal or post-loss CMA requests. These codes help substantiate the clinical rationale for testing.

Include specific O35.xxx codes for suspected fetal anomalies when ordering prenatal CMA
Use O36.4XX for intrauterine death and P95/P02.9 for stillbirth/newborn outcome cases

Documentation Required

Pre-test counseling and specimen collection

Pre-test counseling and specimen collection: Genetic counseling (pre- and post-test) is strongly recommended and often required by professional guidelines. For diagnostic prenatal CMA, ensure that invasive specimen collection (amniocentesis or chorionic villus sampling) is planned and documented because CMA requires fetal DNA from invasive procedures for diagnostic prenatal testing.

Document that pre-test counseling occurred and that invasive sampling (amniocentesis or CVS) is scheduled for diagnostic prenatal CMA
Ensure specimen source (amniotic fluid, CVS, fetal tissue, or POC) is appropriate for CMA testing

Documentation Required

Genetic counseling and informed consent

Genetic counseling and informed consent: Comprehensive pretest and posttest genetic counseling by qualified personnel is essential. Counseling must cover benefits, limitations, possible findings including VUS, non-paternity, consanguinity, and adult-onset conditions. Document face-to-face counseling and signed informed consent (or parental consent/patient assent as applicable).

Pre- and post-test counseling should be provided by genetic counselors, geneticists, or qualified clinicians
Document counseling encounter and informed consent in the medical record prior to testing

Step Therapy

Step therapy

Step therapy: No step therapy requirements are specified for CMA in this section. Follow guideline-based sequencing recommendations where targeted testing for a suspected syndrome is appropriate before ordering CMA.

No formal step therapy or quantity limits stated in this section
If a recognized genetic syndrome is suspected, perform targeted diagnostic testing first; if negative, proceed to CMA per guidelines

Note

Guideline-based sequencing and testing sequence recommendations

Guideline-based sequencing and targeted testing before CMA when syndrome suspected: Follow professional guidance for testing sequence. When a specific genetic syndrome is suspected, order targeted testing (e.g., FMR1 for Fragile X, PTEN testing, etc.) first. If targeted testing is negative or non-diagnostic, proceed to CMA and additional testing (e.g., WES) as indicated.

AACAP, ACMG, and AAN recommend targeted testing for recognized syndromes before CMA when indicated
If targeted syndrome-specific tests are negative, CMA and Fragile X testing are recommended for unexplained DD/ID/ASD
CMA is recommended as first-tier testing for unexplained neurodevelopmental disability and congenital anomalies when a specific syndrome is not suspected

Intellectual Disability: a condition diagnosed before age 18 that includes below-average intellectual function and lack of skills necessary for daily living.

Age boundaryDiagnosis made before age 18 years.

Relevance to testingCMA is recommended as a first‑tier test in evaluation of individuals with ID when a specific syndrome is not suspected.

Intrauterine Fetal Demise / Stillbirth

DefinitionIntrauterine Fetal Demise (Stillbirth): fetal death at or after 20 weeks' gestation.

Clinical contextCMA may be used to evaluate embryos/fetuses in cases of intrauterine fetal demise or stillbirth when a genetic diagnosis is pursued.

Coding supportUse of newborn/stillbirth outcome codes (e.g., P95) and maternal care codes may support documentation and claims.

Well‑Delineated Genetic Syndrome

DefinitionWell‑Delineated Genetic Syndrome: a recognizable collection of traits or abnormalities that tend to occur together and are associated with a specific disease (examples include Down syndrome, Turner syndrome, Rett syndrome, Prader‑Willi, Williams syndrome).

Identification methodsDistinguishing characteristics such as facial features, physical traits, lab tests, or family history can identify a syndrome.

Testing implicationWhen a well‑delineated syndrome is suspected, syndrome‑specific targeted testing is recommended first; CMA is indicated if targeted testing is negative or unrevealing.

O35.* (maternal care for suspected fetal conditions)

DefinitionO35 series: ICD‑10 codes for maternal care for suspected fetal conditions, including suspected chromosomal abnormalities and specific fetal anomalies (e.g., O35.11X* for suspected Trisomy 13, O35.12X* for suspected Trisomy 18, O35.13X* for suspected Trisomy 21).

Use caseThese codes are applied when maternal care is provided for suspected fetal chromosomal or other major anomalies to support diagnostic testing such as CMA.

ExamplesO35.10X* (suspected chromosomal abnormality, unspecified), O35.11X* (Trisomy 13), O35.12X* (Trisomy 18), O35.13X* (Trisomy 21).

Q‑series congenital / chromosomal codes

DefinitionQ‑series codes: ICD‑10 codes for congenital chromosomal abnormalities and syndromic diagnoses (e.g., Q90.* for Trisomy 21, Q91.* for Trisomy 18/13, Q93.* for whole chromosome monosomies and deletions, Q93.51/Q93.52 for Angelman/Phelan‑McDermid).

Clinical relevanceQ‑series codes denote specific chromosomal or syndromic diagnoses and are used to document confirmed congenital chromosomal abnormalities identified by testing such as CMA.

ExamplesQ90.0 (Trisomy 21, nonmosaic), Q91.0 (Trisomy 18), Q93.4 (Deletion of short arm of chromosome 5), Q93.51 (Angelman syndrome).

CMA (Chromosomal microarray analysis)

DefinitionCMA (Chromosomal microarray analysis): laboratory testing using array comparative genomic hybridization (aCGH) and/or SNP array to detect genomic copy number variations (deletions and duplications) and regions of homozygosity across the genome.

ModalitiesIncludes aCGH (comparative hybridization) and SNP array approaches; CMA may be targeted to known regions or genome‑wide.

Clinical applicationUsed in prenatal/fetal evaluations (amniocentesis, CVS, POC), and for postnatal evaluation of DD/ID, ASD, and multiple congenital anomalies.

CNV (Copy number variation)

DefinitionCNV (Copy number variation): genomic alterations that include deletions and/or duplications of one or more sections of DNA that can be benign or pathogenic.

Interpretation guidanceCNV classification categories include pathogenic, benign, and variants of uncertain significance; parental testing may clarify de novo versus inherited status.

Detection methodDetected by CMA platforms (aCGH or SNP array) and may require additional laboratory or parental studies to determine clinical significance.

Limitations of CMA

Key limitationsCMA cannot reliably detect balanced chromosomal rearrangements (no net gain/loss) and may not detect uniparental disomy (UPD) in all cases.

Other limitationsCMA may yield variants of uncertain significance and false positives that require additional testing (karyotype, FISH, parental studies, or sequencing) and counseling.

ImplicationAdditional or alternative testing (karyotype, targeted assays, WES/WGS) may be required to clarify mechanism or detect abnormalities not captured by CMA.

CMA (cytogenetic microarray) — alternate label

Alternate labelCMA (cytogenetic microarray): term used interchangeably with chromosomal microarray analysis and includes aCGH and SNP array methods for CNV detection.

ScopeCytogenetic microarray detects copy number variants and regions of homozygosity; used as first‑line in many postnatal neurodevelopmental evaluations and in specified prenatal settings.

Platform noteDifferent CMA platforms (aCGH versus SNP array) vary in capability (e.g., SNP arrays can detect regions of homozygosity); ordering clinicians should be aware of platform limitations.

CNV classification & follow‑up guidance

Classification guidanceCNVs should be classified as pathogenic, benign, or variants of uncertain significance; parental testing is recommended to determine if a CNV is de novo or inherited to aid interpretation.

Follow-up actionsWhen a CNV of unknown significance is identified, plan and document parental testing and consider cytogenetic/FISH confirmation and genetic counseling.

Reporting standardsLaboratory and professional guidelines recommend specific reporting conventions and follow‑up recommendations for CNV interpretation in clinical reports.