CPT® Code 76817

Quick Reference

• Code definition: Reports a real-time ultrasound of the pregnant uterus performed via transvaginal (endocavitary) approach with permanent image documentation and signed physician interpretation.
• Key billing rule: MUE = 1; only one unit per date of service per provider. Billed globally or with modifier 26 (professional) or TC (technical) depending on practice and setting structure.
• Modifier essentials: Modifier 26 accounts for 82% of claims; TC for facility or equipment-only billing; modifier 59 or XU is required when pairing with a same-day transabdominal OB ultrasound to bypass NCCI PTP bundling edits.
• Documentation must-have: The report must explicitly state the transvaginal approach with cervical assessment, adnexal evaluation, and other transvaginal-specific findings. A combined report that does not distinguish approach will not support separate billing from a transabdominal code.
• Top confusion point: Do not substitute 76817 for 76830 (non-obstetric TVU) or use 76815 (limited transabdominal) when the actual approach was transvaginal. Approach and pregnancy status together determine code selection.
• Payer alert: In the hospital outpatient setting (OPPS), 76817 is STV-Packaged; no separate APC facility payment is made. The professional claim remains separately payable under the Medicare Physician Fee Schedule.

When to Use This Code

CPT 76817 reports a transvaginal ultrasound performed on a pregnant patient, covering a complete real-time examination of the uterus, fetus, and maternal pelvic structures with permanent image storage and a signed written interpretation. The code is approach-specific: any transvaginal obstetric ultrasound maps here, regardless of trimester or indication.

Primary clinical indications:

• Early pregnancy viability assessment (gestational sac, yolk sac, embryonic cardiac activity)
• Suspected ectopic pregnancy with perigestational and adnexal evaluation
• Subchorionic hemorrhage and threatened abortion workup
• Cervical length measurement for preterm birth risk stratification
• Low-lying placenta or placenta previa surveillance (os-to-placenta distance measurement)
• Inadequate transabdominal imaging windows due to obesity, bowel gas, or uterine fibroids
• First-trimester fetal anatomy when transabdominal views are insufficient

Scope boundaries: 76817 covers the full transvaginal examination with image documentation. A bedside "quick look" falls under 76815 regardless of approach. When the specific purpose of the transvaginal scan is nuchal translucency measurement, report 76813, which allows both transabdominal and transvaginal approaches. Non-pregnant pelvic evaluation belongs under 76830. The descriptor requires real-time imaging with archived image documentation; audio-only or real-time without archiving does not meet the code requirement.

Setting and provider context: Physician supervision indicator 01 (general supervision) applies, so a trained sonographer may perform the scan. The interpreting physician must provide the written report. In split-billing environments, modifier 26 (professional) or TC (technical) is required; billing globally in a hospital outpatient setting is a compliance error.

Code Differentiation Table

The critical differentiator between 76817 and 76830 is pregnancy status, not technique. If the patient is pregnant, 76817 is correct regardless of what clinical question drives the transvaginal approach. If the patient is not pregnant, 76830 applies even if the same pathology is being evaluated.

The 76817 versus 76813 distinction catches many first-trimester coders: 76813 allows transvaginal performance, but its purpose is NT measurement as part of first-trimester screening. When a full transvaginal examination is performed for viability or ectopic evaluation in the same encounter as NT measurement, both codes may be reportable when documentation supports distinct clinical purposes for each study.

Billing & Modifier Rules

Modifier 26 and TC: PC/TC Indicator 1 applies to 76817. Modifier 26 (professional component) is appended when the physician provides only the interpretation and report and the technical component belongs to another entity. In private office settings where the physician owns the equipment and employs the sonographer, global billing without a modifier is appropriate. Modifier TC is used by the entity billing only for the technical component. Applying 26 to a globally-owned practice is a systemic underpayment error and vice versa.

Modifier 59 and XU for same-day dual billing: When 76817 is billed on the same date as a transabdominal OB ultrasound code (76801, 76805, or 76811), NCCI PTP edits treat 76817 as a component service. Modifier XU (unusual non-overlapping service) is the preferred NCCI-bypass modifier; modifier 59 is acceptable when no more specific X-modifier applies. The documentation must support separate clinical necessity for both the transvaginal and transabdominal examinations, each with its own documented findings and interpretation. A single report describing both approaches without distinguishing approach-specific findings does not sustain the unbundling.

MUE = 1: Only one unit of 76817 may be reported per date of service per provider, regardless of how many times the probe was repositioned or how many clinical questions were addressed in the single session.

OPPS packaging: In the hospital outpatient setting, 76817 carries APC Status STV-Packaged, meaning no separate facility payment is made. The cost is absorbed into the primary service APC. Facility coders should still report 76817 for data and quality capture, but should not build revenue projections around a separate line-item payment.

Global days = XXX: No surgical global period applies. Pre-operative and post-operative modifiers (24, 57) are not relevant to this code.

Documentation Essentials

Documentation supporting 76817 must establish that a transvaginal approach was used, that a complete real-time examination was performed, and that permanent images were archived with a signed written interpretation.

Required elements:

• Explicit statement of transvaginal approach (not merely "pelvic ultrasound" or "OB ultrasound")
• Gestational age based on LMP or fetal biometric measurements
• Number of fetuses
• Fetal cardiac activity (present or absent)
• Fetal position and presentation
• Placental location, including relationship to internal os when clinically relevant
• Amniotic fluid assessment, qualitative or quantitative
• Cervical appearance and length (particularly relevant for 76817 since transvaginal is the standard method for cervical length measurement)
• Adnexal evaluation (a standard component of the transvaginal exam)
• Maternal pelvic structures as visualized
• Clinical impression and signed interpretation by the interpreting physician

Audit red flags specific to 76817:

A report stating "obstetric ultrasound" without specifying the transvaginal approach cannot distinguish between 76817 and 76815 on audit. Cervical length not documented when cervical surveillance was the stated indication weakens medical necessity. A single combined report covering both a transabdominal and transvaginal exam without separating findings by approach will not withstand review for dual-code billing. Missing image archiving documentation is a descriptor-level compliance gap.

Medical necessity: For routine antenatal encounters, Z34.x supervision codes may trigger frequency review on serial TVU visits. Indication-specific O codes provide stronger medical necessity support: O20.0 for threatened abortion, O26.87x for short cervix, O44.x for placenta previa. Payers conducting post-payment audits look for alignment between the diagnosis code and the documented clinical rationale for choosing the transvaginal approach specifically.

Medicare, Commercial & Medicaid Payer Rules

Medicare:

No national coverage determination exists for obstetric ultrasound. Coverage is determined by MAC-issued local coverage determinations and medical necessity criteria on a claim-by-claim basis. PC/TC Indicator 1 means the code is split-billable; site-of-service payment differentials apply between facility and non-facility rates on the MPFS. OPPS STV-packaged status means no separate facility APC payment. The MUE of 1 is enforced per date of service per provider.

Commercial payers:

First-trimester TVU for viability and ectopic evaluation is broadly covered. Serial TVU for cervical length surveillance or placenta previa follow-up typically requires indication-specific diagnosis codes; Z34.x as the sole diagnosis often triggers automated review or denial on repeat encounters. Some payers require prior authorization for ultrasound beyond their standard frequency allowance per pregnancy. When billing 76817 alongside a transabdominal code, most commercial payers enforce the same NCCI logic and expect separate written interpretations for each study with approach-specific findings.

Medicaid:

Medicaid is the primary payer for obstetric ultrasound, and frequency policies vary significantly by state. Most state programs allow one to three ultrasounds per uncomplicated pregnancy; additional studies require documented medical necessity aligned with a specific obstetric complication code. Serial TVU for cervical length or previa surveillance requires an appropriate O-code diagnosis. Managed Medicaid plans may impose additional prior authorization requirements for repeat exams. Coders should verify the applicable state Medicaid fee schedule and frequency guidance for each jurisdiction where claims are submitted.

Common Denials & Prevention

Denial: Wrong code, non-obstetric patient A claim for 76817 submitted with a non-obstetric diagnosis or no pregnancy indicator will deny because payers expect an obstetric context to validate the code. Prevention: Confirm documented pregnancy and pair with a Z34.x, O-code, or other obstetric diagnosis. If the patient is not pregnant, report 76830.

Denial: Bundled without modifier 76817 billed on the same date as 76801, 76805, or 76811 without modifier 59 or XU triggers NCCI PTP bundling denial. Prevention: Append modifier XU (preferred) or 59 to 76817 when billing same-day with a transabdominal code and ensure separate documentation with distinct findings for each approach. On appeal, CMS NCCI Policy Manual Chapter 9 supports unbundling when both services are medically necessary and separately documented.

Denial: Insufficient documentation Post-payment audits recoup 76817 when the report does not explicitly state the transvaginal approach or does not document the elements expected of a complete obstetric ultrasound examination. Prevention: Structured reporting templates should require transvaginal approach notation, cervical assessment, adnexal evaluation, and signed interpretation as mandatory fields; free-text reports that omit approach create systemic audit exposure.

Denial: Frequency exceeded Medicaid and some commercial plans deny repeat 76817 claims when frequency thresholds are reached without documented medical necessity for the additional study. Prevention: Use the most specific indication diagnosis available rather than routine supervision Z34.x codes for serial monitoring visits. Document the clinical decision-making and findings at each encounter.

Denial: OPPS facility separate billing Hospital outpatient facilities that attempt to collect separate APC payment for 76817 when it is STV-Packaged will see claim reduction. Prevention: Report 76817 for data and quality purposes in the facility setting, but do not expect or project a separate facility line-item payment.

Coding Scenarios

Scenario 1: First-trimester viability and ectopic evaluation, physician-owned practice

A patient at 6 weeks presents with pelvic pain and spotting. The physician performs a transvaginal ultrasound, identifies an intrauterine gestational sac with cardiac activity, evaluates bilateral adnexa (no mass), and documents cervical appearance. A signed written interpretation is completed. The physician owns the equipment and employs the sonographer.

Correct coding: 76817 (global, no modifier) + O20.0

Why: Global billing is correct because the physician owns the technical component. O20.0 (threatened abortion) documents the indication. 76830 would be wrong because the patient is pregnant; 76815 would be wrong because this is a complete documented study, not a limited bedside assessment.

Scenario 2: Cervical length surveillance added to anatomy scan

An 18-week patient with a history of preterm birth undergoes a detailed fetal anatomy survey performed transabdominally (76811) followed by a transvaginal cervical length measurement. Separate reports are generated for each study, each with distinct findings and interpretation.

Correct coding: 76811-26 + 76817-26-XU; ICD-10-CM: Z34.12 + Z36.86

Why: The transabdominal anatomy survey and the transvaginal cervical length exam are clinically distinct services with separate documentation. Modifier XU on 76817 bypasses the NCCI PTP edit. A single combined report without distinguishing findings would not support both codes.

Scenario 3: Hospital outpatient emergency department, ectopic rule-out

A patient presents to the hospital ED with first-trimester pelvic pain. A radiology technologist performs a transvaginal OB ultrasound under general physician supervision; the radiologist interprets and signs the report. An intrauterine pregnancy is confirmed.

Correct coding, professional claim: 76817-26 + Z34.01 (or O00.90 if ectopic was the working diagnosis at time of order)

Correct coding, facility claim: 76817 reported for data capture; no separate APC payment (STV-Packaged)

Why: The radiologist bills the professional component with modifier 26. The facility reports 76817 for quality and data purposes but receives no separate facility payment under OPPS STV-packaged status.

Scenario 4: Serial placenta previa surveillance

A 30-week patient with a previously identified low-lying anterior placenta returns for the second of four scheduled transvaginal evaluations to monitor os-to-placenta distance. No transabdominal scan is performed at this visit.

Correct coding: 76817-26 + O44.12 (complete placenta previa without hemorrhage, second trimester) per documentation

Why: Z34.93 alone does not adequately support medical necessity for serial TVU. The O44.x code establishes the specific indication driving repeat examinations. 76816 (follow-up transabdominal) is incorrect because the approach is transvaginal; 76817 is the only CPT code capturing a transvaginal obstetric ultrasound.

Related Codes

• 76801 — First-trimester transabdominal OB ultrasound, single gestation; most commonly paired with 76817 with modifier XU for same-day cervical evaluation
• 76802 — First-trimester transabdominal OB ultrasound, each additional gestation; add-on to 76801
• 76805 — Second/third trimester transabdominal comprehensive; may be paired with 76817 for cervical length surveillance
• 76811 — Detailed fetal anatomic exam, transabdominal; most common same-day pairing with 76817 when cervical length evaluation is added
• 76813 — Nuchal translucency measurement (transabdominal or transvaginal); report instead of 76817 when NT measurement is the specific clinical purpose
• 76815 — Limited OB ultrasound; the limited bedside alternative; not transvaginal-specific
• 76816 — Follow-up transabdominal OB ultrasound; growth scan follow-up via transabdominal approach
• 76830 — Non-obstetric transvaginal ultrasound; same approach, non-pregnant clinical context

Sources

1. CPT Code 76817 Database Record — Internal CPT database (sourced from AMA CPT): official descriptor, MUE = 1, PC/TC Indicator 1, Global XXX, Supervision indicator 01, OPPS STV-Packaged status, modifier usage statistics, code history (added 2003, description changed 2011)
2. CMS Medicare Physician Fee Schedule — PC/TC Indicator 1, Global XXX, Type of Service 4 (Diagnostic Radiology), OPPS APC Status STV-Packaged confirmed via database record
3. CMS NCCI Policy Manual, Chapter 9: Radiology Services — Bundling principles for same-body-part ultrasound codes; PTP edit modifier bypass requirements using modifier 59 or X-modifiers with separate documentation
4. ACOG Practice Bulletin No. 175: Ultrasound in Pregnancy (2016, reaffirmed) — Clinical indications for transvaginal obstetric ultrasound across trimesters; standard-of-care context
5. ACOG Practice Bulletin No. 130: Prediction and Prevention of Preterm Birth (2012, reaffirmed 2021) — Transvaginal cervical length measurement as standard of care for preterm birth risk stratification