OpenPayer is powered by Trek Health's payer performance platform. Trek continuously ingests, validates, and normalizes Transparency in Coverage data alongside payer policies and other commercial payer data to create a structured payer intelligence foundation. OpenPayer uses this foundation to deliver personalized search results, dynamically generated policy pages, and tailored policy monitoring based on each user's payers, specialties, billing codes, and areas of interest. The same intelligence powers broader payer performance workflows, including reimbursement benchmarking, contract evaluation, payer negotiations, and financial decision-making.

ModifiedUnitedHealthcarePolicy CS017ID.E

Chromosome Microarray Testing (Non-Oncology Conditions) (for Idaho Only)

Customize your policy alerts

Sign up for UnitedHealthcare Policy CS017ID.E alerts

Get alerted when Policy CS017ID.E changes without checking for updates manually.

Monitor payer policy activity

Receive email alerts as soon as relevant payer policies are published or updated.

State-specific UnitedHealthcare medical policy for chromosome microarray testing (aCGH/SNP array) for non-oncology conditions that applies only to Idaho members, including Idaho Medicaid Plus plans, describing coverage rationale, applicable codes, and documentation expectations.

Policy Summary

PayerUnitedHealthcare

PolicyChromosome Microarray Testing (Non-Oncology Conditions) (for Idaho Only)

Policy CodePolicy CS017ID.E

Change TypeDefinitions and terminology clarificationsIdaho-specific code coverage note

Effective DateAug 1, 2026

Last ReviewNov 1, 2025

Next Review Date

Key ActionWhen ordering prenatal CMA for fetal structural abnormalities or stillbirth evaluation, document the indication and include pretest genetic counseling and informed consent.

SourceLink

POLICY UPDATE CHANGES

Added reference link to the Medical Policy titled Genetic Testing for Cardiac Disease (for Idaho Only).

Removed reference link to the Medical Policy titled FDA Cleared or Approved Companion Diagnostic Testing (for Idaho Only).

Removed reference link to the Medical Policy titled Molecular Oncology Testing for Hematologic Cancer Diagnosis, Prognosis, and Treatment Decisions (for Idaho Only).

Replaced reference to 'Multiple anomalies' with 'multiple Congenital Anomalies'.

Replaced reference to 'Developmental Delay' with ' Global Developmental Delay'.

Added definition of Autism Spectrum Disorder and Congenital Anomaly.

Removed definition of 'Prenatal Diagnosis'.

Updated definitions of Global Developmental Delay, Intellectual Disability, and Well-Delineated Genetic Syndrome.

Added notation that CPT/HCPCS codes 0156U, 0209U, and S3870 are not on the State of Idaho Medicaid Fee Schedule and may not be covered.

Updated Description of Services, Clinical Evidence, and References sections to reflect the most current information.

Idaho-onlyState applicability

aCGH/SNPProven test methods

3Idaho Medicaid non-covered codes

20+ICD-10 codes listed

5.72%Pooled CMA yield (select)

Coverage Criteria for Chromosome Microarray Testing (CMA)

Medically Necessary Indications

Covered when ANY of the following specific clinical scenarios apply:

Medically necessary indications: Evaluation of an embryo/fetus in individuals undergoing invasive prenatal diagnostic testing (e.g., amniocentesis, chorionic villus sampling, or fetal tissue sampling).

CMA methods must use array comparative genomic hybridization (aCGH) and/or single-nucleotide polymorphism (SNP) array as described in policy.

Medically necessary indications: Evaluation of individuals with Autism Spectrum Disorder when genetic evaluation for copy number variants is clinically indicated.

CMA is an accepted diagnostic test in neurodevelopmental conditions to support identification of genetic causes.

Medically necessary indications: Evaluation of isolated severe congenital heart disease (CHD) detected prenatally or postnatally when genetic testing for chromosomal abnormalities is indicated.

Policy Summary

PayerUnitedHealthcare

PolicyChromosome Microarray Testing (Non-Oncology Conditions) (for Idaho Only)

Policy CodePolicy CS017ID.E

Change TypeDefinitions and terminology clarificationsIdaho-specific code coverage note

Effective DateAug 1, 2026

Last ReviewNov 1, 2025

Next Review Date

Key ActionWhen ordering prenatal CMA for fetal structural abnormalities or stillbirth evaluation, document the indication and include pretest genetic counseling and informed consent.

SourceLink

On This Page

Evidence supports CMA yield in CHD, particularly when extracardiac anomalies are present.

Medically necessary indications: Evaluation of multiple congenital anomalies that are not specific to a well-delineated genetic syndrome and cannot be identified by clinical evaluation alone.

CMA is indicated when multiple congenital anomalies are present and a specific syndrome is not suspected.

Medically necessary indications: Evaluation of global developmental delay or intellectual disability in individuals <5 years (global developmental delay) or older when a specific syndrome is not suspected.Age < 5 years for global developmental delay definition (where applicable)

CMA is appropriate when a specific syndrome is not suspected by clinical assessment.

Not Medically Necessary / Unproven

Unproven / Not medically necessary: Chromosome microarray testing (aCGH or SNP array) is unproven and not medically necessary for indications and populations not listed in the medically necessary criteria above due to insufficient evidence of efficacy.

Includes routine screening in pregnancies without indications for invasive diagnostic testing and indications limited to maternal serum screening without other abnormal findings.

Situations where CMA provides incremental diagnostic yield and is supported by evidence

Evidence supports CMA in prenatal settings particularly when certain clinical features are present; summarized as findings from systematic reviews and cohort studies.

Evidence-supported prenatal situations: CMA provides incremental diagnostic yield beyond conventional karyotype in: (1) fetal growth restriction (FGR), with greatest yield when structural malformations are present; (2) increased nuchal translucency in early pregnancy; (3) fetal congenital heart defects (especially CHD with extracardiac anomalies and certain CHD subtypes, e.g., septal defects); and (4) abnormal ultrasound findings or abnormal noninvasive prenatal testing (NIPS) results.See supporting studies for quantitative incremental yields (e.g., FGR strata 3%–10%; nuchal translucency CNV rate ~4.3%; CHD CMA yield up to ~15% overall and higher with extracardiac anomalies).

Estimates derive from meta-analyses and observational cohorts; yields vary by phenotype severity and coexisting anomalies.

Covered prenatal indications

Covered when consistent with major professional society recommendations for prenatal diagnostic testing

Fetal structural anomaly on ultrasound: When an invasive prenatal diagnostic procedure is performed for a fetus with one or more structural abnormalities identified on ultrasound, CMA is recommended and may replace conventional karyotype as the primary diagnostic test.

ACOG: CMA should be the primary test for fetal structural abnormalities; SMFM/SOGC guidance aligns with offering CMA in these cases and replacing karyotype where appropriate.

Fetal growth restriction (FGR): Offer prenatal diagnostic testing including CMA when FGR is detected in association with fetal malformation or polyhydramnios, and offer CMA when unexplained isolated FGR is diagnosed at <32 weeks' gestation.Gestational age < 32 weeks for consideration in isolated FGR

SMFM Consult Series recommends offering CMA in these scenarios.

Stillbirth / intrauterine fetal death: CMA should be incorporated into the stillbirth workup and performed after appropriate parental permission, as it improves test success rate and genetic anomaly detection compared with karyotype.Fetal death ≥ 20 weeks for stillbirth context per guidance

ACOG/SMFM recommend genetic analyses in all cases of stillbirth with parental permission (strong recommendation).

Invasive prenatal testing regardless of maternal age: CMA should be made available to any patient undergoing invasive diagnostic testing; many CMA-detected changes are not associated with increasing maternal age.

ACOG guidance supports offering CMA to all women choosing invasive diagnostic testing regardless of age.

Increased nuchal translucency: Offer CMA for fetuses with increased nuchal translucency (e.g., ≥ 3.5 mm) measured in the first trimester, recognizing higher adverse outcome rates with persistence and with thicker measurements.Nuchal translucency ≥ 3.5 mm

SOGC/CCMG and meta-analyses support offering CMA in this setting.

Invasive prenatal diagnostic evaluation (amniocentesis, CVS, fetal tissue sampling)

Invasive prenatal diagnostic evaluation: Chromosome microarray testing is indicated when performed on samples obtained via invasive prenatal diagnostic procedures (amniocentesis, chorionic villus sampling) or fetal tissue sampling as part of diagnostic evaluation.

Policy specifies aCGH and/or SNP arrays as the CMA methods of choice for these indications.

Autism Spectrum Disorder

Autism Spectrum Disorder: CMA is indicated for individuals undergoing genetic evaluation for Autism Spectrum Disorder to detect copy number variants and other chromosomal abnormalities that may underlie the condition.

CMA supports diagnosis of genetic causes of Autism Spectrum Disorder as noted in clinical description.

Isolated severe congenital heart disease

Isolated severe congenital heart disease: CMA is indicated for evaluation of isolated severe congenital heart disease detected prenatally or postnatally when genetic testing for chromosomal abnormalities is clinically warranted; yield is higher when extracardiac anomalies coexist.

Meta-analyses and cohort studies report substantially increased detection rates in CHD with extracardiac anomalies and recommend CMA if karyotype or FISH is normal; some authors recommend CMA as first-tier for CHD.

Multiple congenital anomalies not specific to a well-delineated genetic syndrome

Multiple congenital anomalies: CMA is indicated for evaluation of multiple congenital anomalies not specific to a well-delineated genetic syndrome and not identifiable by clinical evaluation alone.

Professional guidance and the policy specify CMA when multiple congenital anomalies are present and a specific syndrome is not suspected.

Global developmental delay/intellectual disability when a specific syndrome is not suspected

Global developmental delay / intellectual disability: CMA is indicated for individuals with global developmental delay (typically defined <5 years of age) or intellectual disability when a specific genetic syndrome is not suspected based on clinical evaluation.Age < 5 years (global developmental delay definition) where applicable

CMA is accepted for evaluating genetic causes of global developmental delay and intellectual disability.

Multiple maternal-fetal conditions and congenital anomalies (ICD-10 O35.*, Q* codes) associated with potential use of CMA

Maternal-fetal conditions and congenital anomalies (ICD-10 O35.*, Q* codes): Chromosome microarray testing may be used when clinical indications correspond to the listed maternal-fetal and congenital anomaly ICD-10 codes (O35.* and Q* codes) that reflect suspected fetal malformations or hereditary disease.

Applicable codes are provided in the policy's coding sections to guide claim/authorization processes.

Prenatal invasive testing for abnormal ultrasound findings, congenital heart defects (esp. with extracardiac anomalies), fetal growth restriction with structural malformations, abnormal NIPT, and evaluation of products of conception

Prenatal invasive testing for abnormal findings: When invasive prenatal diagnostic testing is performed for abnormal ultrasound findings (including congenital heart defects, especially with extracardiac anomalies), fetal growth restriction with structural malformations, abnormal noninvasive prenatal screening (NIPS) results, or evaluation of products of conception, CMA is an appropriate diagnostic test due to increased diagnostic yield compared with karyotype.

Studies and guidelines support CMA in these prenatal contexts and describe variable incremental yields based on phenotype.

Fetal structural anomalies detected on ultrasound

Fetal structural anomalies detected on ultrasound: When a fetal structural anomaly is identified on ultrasound and invasive prenatal diagnosis is performed, CMA should be the primary test and can replace karyotype as the first-tier diagnostic assay.

ACOG and SOGC/CCMG recommend CMA as primary test for prenatal diagnosis in the setting of fetal structural anomalies.

Stillbirth/intrauterine fetal death

Stillbirth / intrauterine fetal death: CMA is recommended as part of the stillbirth workup and should be performed after obtaining appropriate parental permission because it improves detection of genetic anomalies and test success rates compared with karyotype.Fetal death ≥ 20 weeks for stillbirth context (per guideline definitions)

ACOG/SMFM recommend genetic testing in stillbirths (strong recommendation, high-quality evidence).

All indications not explicitly enumerated as medically necessary in this policy are considered unproven and not medically necessary. The policy states that chromosome microarray testing (aCGH or SNP array) is proven and medically necessary only for the listed populations (for example, invasive prenatal diagnostic evaluation and certain developmental, congenital, or neurodevelopmental indications), and that use of CMA for all other populations and conditions is unproven due to insufficient evidence of efficacy.

Evidence summarized in the clinical‑evidence sections demonstrates that indication patterns strongly affect diagnostic yield—studies reporting zero pathogenic findings in maternal serum screening–only cases and a very low clinically significant CNV detection rate in unselected pregnancies support restricting routine use of CMA to the enumerated medically necessary indications and individualized diagnostic contexts.

Preimplantation genetic testing is not covered under this policy and is addressed separately. Refer to the Medical Policy titled Preimplantation Genetic Testing and Related Services (for Idaho Only) for coverage criteria and operational details for embryo testing prior to transfer.

This policy’s coverage rationale applies to chromosome microarray testing performed in clinical diagnostic contexts (e.g., invasive prenatal testing, developmental or congenital indications); preimplantation procedures follow the separate referenced policy.

No explicit universal exclusions beyond the statement that testing is unproven for populations not listed as medically necessary are provided in the policy excerpts. The document notes applicable diagnosis codes but does not list additional operational exclusions in the provided sections.

Providers should consult plan‑specific documents and the Idaho Medicaid Provider Handbook for any state or contractual exclusions that are not enumerated within this policy.

In one cohort described in the clinical evidence, chromosome microarray testing did not identify pathogenic findings in cases prompted solely by maternal serum screening—none of the 29 such cases had pathogenic CNVs on CMA. The authors used this observation to illustrate how lower‑yield indication patterns relate to routine practice outcomes and to highlight limitations of single‑center, observational data.

This finding supports the policy’s position that CMA should be targeted to the specified medically necessary indications rather than applied broadly to low‑yield screening indications.

Systematic review and meta‑analysis data indicate that routine CMA screening in pregnancies not selected for increased risk yields a low rate of clinically significant copy number variants—CMA identified a clinically significant CNV in 0.84% (95% CI, 0.55%–1.30%) of fetuses in the largest studies pooled. The authors concluded that this low yield supports counseling about individualized risk rather than routine CMA for pregnancies without indications for invasive testing.

Because the background risk of common aneuploidies differs from the background risk of pathogenic CNVs detected by CMA, the review recommends informing all women of their overall individual risk of chromosomal aberrations rather than relying solely on trisomy risk estimates.

Per the policy history and applicable codes section, CPT/HCPCS codes 0156U, 0209U, and S3870 are not listed on the State of Idaho Medicaid Fee Schedule and therefore may not be covered by the State of Idaho Medicaid Program. Providers serving Idaho Medicaid members should consult the Idaho Medicaid Provider Handbook for non‑covered and excluded services guidance and for plan‑specific billing rules.

When billing or seeking reimbursement for these codes for Idaho Medicaid members, verify state fee‑schedule coverage before assuming reimbursement and follow any applicable prior authorization or plan procedures described elsewhere.

Procedure and Diagnosis Codes

Procedure CPT codesCPT

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

HCPCSHCPCS

S3870

Comparative genomic hybridization (CGH) microarray testing for developmental delay, autism spectrum disorder and/or intellectual disability

ICD-10 codes (examples listed across multiple pages)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.
F84.0	Autistic disorder.
N96	Recurrent pregnancy loss.
O02.1	Missed abortion.

1–10 of 20

1/2

Applicable ICD-10 CodesICD-10

O35.05X9	Maternal care for (suspected) central nervous system malformation or damage in fetus, holoprosencephaly, other fetus
O35.06X0	Maternal care for (suspected) central nervous system malformation or damage in fetus, hydrocephaly, not applicable or unspecified
O35.06X5	Maternal care for (suspected) central nervous system malformation or damage in fetus, hydrocephaly, fetus 5
O35.06X9	Maternal care for (suspected) central nervous system malformation or damage in fetus, hydrocephaly, other fetus
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

1–10 of 200

1/20

Applicable ICD-10 Codes (excerpt)ICD-10

O36.4XX4	Maternal care for intrauterine death, fetus 4.
O36.4XX5	Maternal care for intrauterine death, fetus 5.
O36.4XX9	Maternal care for intrauterine death, other fetus.
P95	Stillbirth.
Q20.1	Double outlet right ventricle.
Q21.0	Ventricular septal defect.
Q21.11	Secundum atrial septal defect.
Q23.4	Hypoplastic left heart syndrome.
Q90.0	Trisomy 21, nonmosaicism.
Q91.0	Trisomy 18, nonmosaicism.

1–10 of 16

1/2

Applicable CPT/HCPCS codes with Idaho Medicaid coverage noteCPT

0156U	CPT/HCPCS code noted (not on Idaho Medicaid Fee Schedule)
0209U	CPT/HCPCS code noted (not on Idaho Medicaid Fee Schedule)
S3870	CPT/HCPCS code noted (not on Idaho Medicaid Fee Schedule)

Age threshold for Global Developmental Delay — definition note (< 5 years)

DefinitionGlobal Developmental Delay: failure to meet expected developmental milestones in several areas of intellectual functioning in an individual younger than 5 years of age.

Age threshold (actionable)Applies to individuals younger than 5 years — use this age threshold when coding or applying coverage criteria for global developmental delay indications.

ContextUsed to distinguish Global Developmental Delay from intellectual disability for coverage decisions and to guide appropriate use of chromosome microarray testing (CMA).

CNV size threshold referenced — < 10 megabases used in analyses

CNV size thresholdSubmicroscopic copy number variants defined as < 10 megabases (Mb) were used to calculate incremental diagnostic yield of CMA beyond karyotype.

Analytic useThis < 10 Mb threshold was applied in pooled analyses and stratified yield estimates in FGR studies to define clinically significant submicroscopic CNVs.

Interpretation guidanceWhen reporting or counseling on incremental CMA yield, reference the < 10 Mb definition for submicroscopic CNVs as per the cited meta-analysis.

Provider Actions, Documentation, and Consent

Prior Authorization

Procedure codes listed; follow applicable prior authorization rules

Procedure codes for chromosome microarray and related genomic services are listed for reference; providers should follow applicable UnitedHealthcare/Idaho Medicaid prior authorization processes as required by the member's benefit plan.

Listed procedure codes: 0156U, 0209U, 81228, 81229, 81349, 81479, S3870

Prior Authorization

No prior authorization specified in excerpt

The provided sections do not state any specific prior authorization requirements for chromosome microarray testing; only applicable diagnosis and procedure codes are listed in this excerpt.

Prior Authorization

No specific CPT/HCPCS requiring prior authorization in excerpt

This excerpt does not identify particular CPT/HCPCS codes that require prior authorization; the policy provides code lists for reference but defers to federal, state, or contractual coverage rules.

Documentation Required

Document indications when ordering prenatal CMA

When CMA is ordered as the primary prenatal diagnostic test for fetal structural abnormalities or as part of stillbirth evaluation, document the indication (e.g., structural anomalies, fetal growth restriction, stillbirth) and prior diagnostic steps in the medical record to support the request.

Document the fetal indication prompting invasive testing (abnormal ultrasound, FGR, stillbirth).
Record prior diagnostic steps (e.g., karyotype, rapid aneuploidy testing, NIPS) when applicable.

Note

Verify governing coverage requirements and tools

Check federal, state, or contractual requirements and any applicable utilization tools (e.g., InterQual) when determining coverage; in the event of conflict, those requirements govern over this policy.

Note

Evidence: CMA provides incremental diagnostic yield over karyotype

Clinical evidence shows CMA yields incremental diagnostic findings beyond karyotype, particularly in fetuses with FGR plus structural malformations, increased nuchal translucency, and congenital heart defects with extracardiac anomalies, supporting CMA use when karyotype is limited.

Sapantzoglou et al. (2026): incremental yields in FGR strata (3%–10% depending on structural anomalies).
Matarrelli et al. (2025): CNVs detected in 4.3% with increased early nuchal translucency.
Lu et al. (2024): CMA yield 15.3% vs karyotype 8.3% in fetal CHD.

Step Therapy

Follow reflex/confirmatory CMA testing pathways per ACMG

Follow reflex and confirmatory testing pathways: ACMG states CMA may be used as a reflex after a normal karyotype or to confirm abnormal NIPS results; ordering should follow appropriate reflex/confirmatory workflows.

Use CMA to confirm small CNV findings reported on NIPS or as a reflex to a normal karyotype when indicated.

Documentation Required

Required clinical documentation in the medical record

The patient's medical record must include relevant medical history, physical examination, and results of pertinent diagnostic tests or procedures that fully support the medical necessity for the requested CMA.

Include documentation of the clinical indication, prior test results, and specimen source (amniocentesis, CVS, products of conception).

Documentation Required

Document ultrasound phenotype or indication when applicable

Studies and cohorts link testing indications to ultrasound phenotypes; document the specific indication (for example, the ultrasound phenotype) on the requisition and in the record to support testing rationale and interpretation.

Record ultrasound findings or phenotype (e.g., CHD with extracardiac anomalies, increased nuchal translucency) that prompted CMA.

Documentation Required

Document comprehensive pretest and post-test genetic counseling

Comprehensive pretest and post-test genetic counseling by a provider with genetics expertise is essential and should be documented when ordering prenatal CMA.

Counseling should cover benefits, limitations, possible VUS, nonpaternity, consanguinity, and potential adult-onset findings.
Documentation of counseling and informed consent should be included in the medical record.

Note

Use federal/state/contractual requirements when deciding coverage

When making coverage determinations, reference federal, state, or contractual requirements for the member's benefit plan as they may differ from UnitedHealthcare policy; those requirements govern if there is a conflict.

Denial Risk

Denial risk: insufficient documentation

Lack of medical record documentation that supports medical necessity may result in denial of the request or a request for additional records.

Denial Risk

Denial risk for indications outside covered populations

Tests ordered for indications outside the enumerated medically necessary populations (prenatal invasive testing; ASD; isolated severe CHD; multiple congenital anomalies; global developmental delay/intellectual disability when a specific syndrome is not suspected) are considered unproven and may be denied.

Documentation Required

Informed consent and counseling required before prenatal CMA

Obtain informed consent prior to ordering prenatal CMA; consent should include discussion of the potential to identify variants of uncertain significance, nonpaternity, consanguinity, and adult-onset disease.

Do not order prenatal CMA without documented informed consent and counseling.

Billing Rule

Idaho Medicaid: certain codes may not be covered

CPT/HCPCS codes 0156U, 0209U, and S3870 are not on the State of Idaho Medicaid Fee Schedule and therefore may not be covered by Idaho Medicaid; providers should consult the Idaho Medicaid Provider Handbook for non-covered/excluded services.

Codes specifically noted as possibly not covered on the Idaho Medicaid Fee Schedule: 0156U, 0209U, S3870

Step Therapy

Refer to fetal medicine specialists and genetic counseling for early/complex prenatal findings

Refer patients with early increased nuchal translucency or other complex prenatal findings to fetal medicine specialists and genetic counseling for evaluation and test planning.

Referral to fetal medicine specialists and genetics is recommended when early nuchal translucency is detected or when ultrasound findings are complex.

Step Therapy

Specialist consultation recommended before ordering CMA for complex prenatal findings

For complex prenatal findings, ordering of CMA should follow consultation with fetal medicine or genetics specialists; studies encourage specialist referral for decision-making about invasive testing and CMA use.

Ordering should follow specialist consultation and informed consent.

Documentation Required

Follow professional society guidance for counseling and ordering

ACOG/SMFM and SOGC recommend that counseling and testing decisions be made by qualified personnel; ordering should follow consultation and documented informed consent with pre- and post-test counseling provided by trained genetics personnel.

Pre- and post-test counseling should be delivered by trained genetic counselors, geneticists, or providers with genetics expertise.
Document counseling and consent in the medical record when ordering CMA.

Not Covered / Unproven Uses

Chromosome microarray testing for indications that are not listed in the policy's medically necessary indications section is considered not covered (unproven and not medically necessary). This includes any use outside the enumerated conditions such as invasive prenatal evaluation, specified neurodevelopmental disorders, severe isolated CHD, multiple congenital anomalies, and global developmental delay when a specific syndrome is not suspected.

Evidence from an observational cohort reported that CMA identified no pathogenic findings among cases prompted solely by maternal serum screening (29 cases). This nuance supports the policy position that CMA is not routinely indicated for maternal serum screening–only indications and may influence a decision not to cover such uses.

Meta-analytic data demonstrate that routine use of CMA in pregnancies without specific indications for invasive testing and without structural anomalies yields clinically significant findings infrequently (0.84%) and therefore is not routinely indicated; coverage decisions should account for this low diagnostic yield and include counseling about expected outcomes.

The policy history indicates that CPT/HCPCS codes 0156U, 0209U, and S3870 are not on the State of Idaho Medicaid Fee Schedule and may not be covered by Idaho Medicaid. Providers billing Idaho Medicaid should verify coverage and payment policies via the Idaho Medicaid Provider Handbook.

Definitions

Autism Spectrum Disorder

DefinitionAutism Spectrum Disorder: a condition marked by enduring problems communicating and interacting with others, along with restricted and repetitive behavior, interests, or activities (per policy Definitions and recognized diagnostic sources).

Policy relevanceListed as a covered indication for CMA when evaluation for genetic causes is appropriate.

Supporting test roleCMA can support diagnosis of genetic causes of autism spectrum disorder in neurodevelopmental evaluations.

Global Developmental Delay

DefinitionGlobal Developmental Delay: failure to meet expected developmental milestones in several areas of intellectual functioning in an individual younger than 5 years of age.

Age cutoffApplies to individuals younger than 5 years.

Coverage noteIncluded among indications for CMA when a specific syndrome is not suspected.

Well‑Delineated Genetic Syndrome

DefinitionWell‑Delineated Genetic Syndrome: a syndrome characterized by a collection of recognizable traits or abnormalities that tend to occur together and are associated with a specific disease; distinguishing features, laboratory tests, or family history can identify the syndrome.

Clinical implicationIf a well‑delineated genetic syndrome is suspected, testing strategies may follow syndrome‑specific guidance rather than broad CMA alone.

Policy placementPolicy differentiates multiple congenital anomalies not specific to a well‑delineated genetic syndrome as an indication for CMA.

Chromosomal microarray (CMA)

DefinitionChromosomal microarray (CMA): a high‑resolution molecular test used to detect chromosomal abnormalities, including copy number variants (CNVs) and other genomic alterations such as uniparental disomy.

Test modalitiesIncludes array comparative genomic hybridization (aCGH) and single nucleotide polymorphism (SNP) arrays; low‑pass sequencing analysis also referenced in coding descriptors.

Clinical advantageOffers greater sensitivity than conventional karyotype by detecting submicroscopic deletions and duplications.

Incremental diagnostic yield

DefinitionIncremental diagnostic yield: the proportion of additional pathogenic findings (submicroscopic CNVs) detected by CMA after a normal karyotype.

ApplicationUsed to quantify added diagnostic value of CMA in fetal growth restriction and other prenatal indications.

Example metricsMeta-analyses report incremental yields varying by phenotype (e.g., 3%–10% in FGR strata per Sapantzoglou et al.).

VUS rates and context (CMA vs WES)

VUS definition/contextVariant of uncertain significance (VUS): a genetic variant whose association with disease is unclear; CMA and WES report VUS in prenatal testing contexts.

Reported ratesPolicy notes VUS rates in fetal structural anomalies: CMA ~2.86% and WES ~8.32% (contextual comparison in clinical evidence discussion).

Counseling implicationPretest counseling should include discussion of possible VUS results, incidental findings (nonpaternity, consanguinity), and adult‑onset disease.

Autism Spectrum Disorder — Idaho definition update

Updated definition (Idaho variant)Autism Spectrum Disorder: added/updated in the policy Definitions section; policy references standard diagnostic sources (ICD/DSM) for characterization.

Policy change noteDefinitions section updated in the Idaho variant to add Autism Spectrum Disorder wording and align terminology used in Coverage Rationale.

Clinical impactClarifies Autism Spectrum Disorder as a covered indication in the Idaho‑specific policy variant.

Congenital Anomaly — Idaho definition added

Definition added (Idaho variant)Congenital Anomaly: a physical developmental defect present at birth and identified within the first 12 months of birth (as defined in policy Definitions).

Policy noteAdded to Definitions section in the Idaho variant; used in coverage rationale for prenatal evaluation contexts.

RelevanceSupports application of CMA in prenatal cases with congenital anomalies identified on ultrasound.

Global Developmental Delay — Idaho definition update

Updated definition (Idaho variant)Global Developmental Delay: definition updated in the policy's Definitions section to current wording; retains the age threshold of <5 years.

Terminology changePolicy revisions clarified terminology (e.g., replaced 'Developmental Delay' with 'Global Developmental Delay').

Coverage relevanceUsed to define eligibility for CMA when a specific syndrome is not suspected.

Intellectual Disability — Idaho definition update

Updated definition (Idaho variant)Intellectual Disability: definition updated in the policy's Definitions section to current wording describing childhood‑onset neurodevelopmental disorder with intellectual and adaptive functioning difficulties.

Clinical linkageListed with Global Developmental Delay and Autism Spectrum Disorder as neurodevelopmental conditions for which CMA may aid diagnosis.

Source referenceDefinition cites American Psychiatric Association (2013) as used in the policy Definitions.

Well‑Delineated Genetic Syndrome — Idaho definition update

Updated definition (Idaho variant)Well‑Delineated Genetic Syndrome: definition updated to current wording describing a recognizable collection of traits or abnormalities identified by features, tests, or family history.

Policy implicationPolicy distinguishes anomalies that are not specific to a well‑delineated genetic syndrome as an indication for CMA.

ReferenceDefinition aligns with Talking Glossary of Genomic and Genetic Terms (2025) as cited in the policy.

Applicable Codes

Applicable Codes headerApplicable Codes: the following ICD‑10 diagnosis codes are considered relevant to the policy's coverage context and are listed in the policy's coding section.

UseServes as the header indicating ICD‑10 codes (O35.*, Q*, etc.) that map to prenatal and congenital anomaly indications for CMA.

Provider actionReference the policy's Applicable Codes list when documenting indication for testing and prior authorization, if required.

Eligibility Requirements and Scope

The excerpt does not specify formal eligibility criteria beyond the listed medically necessary indications. Professional guidance referenced in the policy emphasizes individualized pretest and post‑test genetic counseling by providers with genetics expertise and consideration of parental testing when a CNV is identified; documentation of counseling and clinical indication should be included in the medical record to support medical necessity.

No discrete eligibility checklist is provided in these sections. Consistent with major society guidance cited in the policy, ordering prenatal CMA should follow consultation with qualified personnel, informed consent that addresses potential findings (including variants of uncertain significance, nonpaternity, and adult‑onset disease), and documentation of the clinical indication and counseling in the medical record.

The document excerpt does not contain top‑level, itemized eligibility nodes or a formal gating checklist for coverage; instead, applicable ICD‑10 codes are provided elsewhere for reference and adjudication purposes.

Similarly, the excerpt includes lists of applicable diagnosis codes but does not present explicit top‑level eligibility nodes or additional administrative criteria in the provided sections.

Background and Clinical Context

Chromosome microarray testing (CMA), including array comparative genomic hybridization (aCGH) and single‑nucleotide polymorphism (SNP) array platforms, is a high‑resolution molecular assay used to detect chromosomal abnormalities such as copy number variants (CNVs) and other genomic alterations including uniparental disomy. CMA offers greater sensitivity and higher resolution than conventional karyotyping, and it is used for prenatal diagnosis (amniocentesis/CVS), evaluation of pregnancy loss, and assessment of neurodevelopmental disorders.

Revision History and Policy Changes

2026-08-01policy_revisionLatest

Policy updated: added a reference to the Medical Policy 'Genetic Testing for Cardiac Disease (for Idaho Only)'; removed references to two Idaho-only policies (FDA Cleared or Approved Companion Diagnostic Testing; Molecular Oncology Testing for Hematologic Cancer Diagnosis, Prognosis, and Treatment Decisions); clarified terminology in Coverage Rationale by replacing 'Multiple anomalies' with 'multiple Congenital Anomalies' and 'Developmental Delay' with 'Global Developmental Delay'; added definitions for Autism Spectrum Disorder and Congenital Anomaly; removed the definition of 'Prenatal Diagnosis'; updated definitions of Global Developmental Delay, Intellectual Disability, and Well-Delineated Genetic Syndrome; added notation that CPT/HCPCS codes 0156U, 0209U, and S3870 are not on the Idaho Medicaid Fee Schedule and may not be covered; and updated Description of Services, Clinical Evidence, and References sections.