Summary & Overview
CPT 0488U: Unity Fetal Antigen NIPT for Alloimmunization
CPT code 0488U designates a Proprietary Laboratory Analysis (PLA) for the Unity Fetal Antigen™ NIPT from BillionToOne Laboratory. This cell–free DNA sequencing test detects specific fetal antigens (Rh, C, c, D, E, Duffy (Fya), and Kell (K)) in pregnancies complicated by maternal alloimmunization to identify fetuses at risk for Hemolytic Disease of the Fetus and Newborn (HDFN). As a PLA code tied to a single manufacturer and assay, CPT code 0488U clarifies coding for payers and providers when reporting this proprietary prenatal screening.
Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The publication provides a national overview of clinical context, coding considerations, and typical sites of service for this lab-based prenatal screening. Readers will find concise benchmarks and policy context relevant to coverage and billing of proprietary noninvasive prenatal tests, an explanation of the clinical utility in alloimmunized pregnancies, and what payers commonly evaluate when considering coverage for PLA-designated assays. Data not available in the input are identified explicitly where applicable.
Billing Code Overview
CPT code 0488U is a Proprietary Laboratory Analyses (PLA) code that applies exclusively to the Unity Fetal Antigen™ NIPT offered by BillionToOne Laboratory, BillionToOne Inc. The test uses cell–free DNA sequencing from maternal blood to detect the presence or absence of specific fetal antigens — including Rh, C, c, D, E, Duffy (Fya), and Kell (K) — for pregnancies in which the pregnant person has alloimmunization. The result helps identify pregnancies at increased risk for Hemolytic Disease of the Fetus and Newborn (HDFN) and guides which pregnancies will most benefit from additional fetal monitoring.
Service type: Proprietary noninvasive prenatal screening using cell–free DNA sequencing
Typical site of service: Clinical laboratory processing with blood draw performed in outpatient phlebotomy settings, obstetrics clinics, or hospital outpatient departments
Clinical & Coding Specifications
Clinical Context
A pregnant patient with a history of red blood cell alloimmunization presents for risk stratification of Hemolytic Disease of the Fetus and Newborn (HDFN). The ordering clinician—typically a maternal-fetal medicine specialist, obstetrician, or an obstetric nurse practitioner—documents maternal antibody specificity (for example, anti-D, anti-Kell, anti-c) and gestational age. A maternal blood sample is collected and sent to BillionToOne Laboratory for the proprietary Unity Fetal Antigen™ NIPT reported under 0488U. The laboratory performs cell-free DNA sequencing to determine presence or absence of fetal antigens (Rh, C, c, D, E, Duffy (Fya), Kell (K)). Results are returned to the ordering clinician who uses the information to decide need and timing for targeted fetal monitoring (ultrasound Doppler surveillance for middle cerebral artery peak systolic velocity), intrauterine intervention, or postpartum neonatal planning. Typical sites of service include outpatient obstetrics clinics, maternal-fetal medicine clinics, and hospital outpatient laboratories. The service type is laboratory genetic testing/Proprietary Laboratory Analysis (PLA) for prenatal alloimmunization assessment.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional interpretation component if the lab separates professional and technical components and the provider is billing for interpretation. |
TC | Technical component | Use when billing only the technical component (laboratory processing) as applicable to the performing lab. |
59 | Data not available in the input. | Data not available in the input. |
QX | Data not available in the input. | Data not available in the input. |
QY | Data not available in the input. | Data not available in the input. |
AS | Data not available in the input. | Data not available in the input. |
CO | Data not available in the input. | Data not available in the input. |
CQ | Data not available in the input. | Data not available in the input. |
QK | Data not available in the input. | Data not available in the input. |
FY | Data not available in the input. | Data not available in the input. |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
| 207Q00000X | Maternal-Fetal Medicine | Specialist managing alloimmunized pregnancies and ordering advanced fetal antigen testing. |
| 207R00000X | Obstetrics & Gynecology | OB/GYNs commonly order prenatal genetic and antigen testing for pregnancy management. |
| 363L00000X | Clinical Laboratory | Laboratory director or clinical genetic testing specialists overseeing NIPT and sequencing assays. |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
O36.0X0 | Maternal care for known or suspected fetal problems, unspecified trimester | Used when close fetal surveillance is required due to alloimmunization risk and fetal antigen testing is ordered. |
O36.012 | Maternal care for known or suspected fetal problems, first trimester | Applicable when antigen status testing is performed early in pregnancy to inform monitoring. |
O36.013 | Maternal care for known or suspected fetal problems, second trimester | Applicable when fetal antigen testing guides mid-pregnancy surveillance and interventions. |
O36.014 | Maternal care for known or suspected fetal problems, third trimester | Applicable when late pregnancy antigen status informs delivery and neonatal planning. |
D75.2 | Other secondary polycythemia | Included as a related hematologic consideration in cases with significant fetal hemolysis though less commonly coded directly; relates to HDFN consequences. |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
0488U | Unity Fetal Antigen™ NIPT (BillionToOne) — cell-free DNA sequencing to detect fetal antigens (Rh, C, c, D, E, Fya, K) in maternal blood for alloimmunization management | Primary PLA code for this proprietary fetal antigen NIPT. |
82105 | Assay of maternal blood for presence of fetal red blood cell antigen (example general immunoassay) | May be used historically for serologic antigen testing; sometimes ordered in parallel in non-sequencing workflows. |
0100U | Data not available in the input. | Data not available in the input. |
0101U | Data not available in the input. | Data not available in the input. |
81420 | Targeted sequence analysis for fetal single-gene disorders (example) | Other molecular prenatal tests that may be ordered in pregnancies at genetic risk; not specific to antigen detection but related in prenatal sequencing workflows. |