CPT code 58340: Hysterosalpingography and SIS billing guide

Key takeaways

CPT code 58340 covers catheterization and introduction of saline or contrast material for saline infusion sonohysterography (SIS) or hysterosalpingography (HSG). The imaging component is billed separately.

For fluoroscopic HSG, pair 58340 with CPT 74740. For ultrasound-guided SIS, pair it with CPT 76831. Using 76830 or 76856 instead of 76831 in SIS workflows is the most common coding error.

The global period for CPT 58340 is 000 days, so no pre- or post-operative services are bundled. Modifier -26 applies when only the professional component is performed.

Pabau’s claims management software supports OB/GYN and fertility billing workflows, helping practices apply correct code pairs and modifier logic before claims reach the payer.

CPT code 58340 covers catheterization and introduction of saline or contrast material for saline infusion sonohysterography (SIS) or hysterosalpingography (HSG). That wording is the official descriptor from the American Medical Association (AMA), which maintains the CPT code set. The code sits in the Introduction Procedures on the Corpus Uteri subsection.

Clinically, 58340 captures the work of placing a catheter through the cervix. The catheter then introduces either sterile saline (for SIS) or iodinated contrast dye (for HSG). It is ordered to evaluate the uterine cavity and fallopian tubes. The usual contexts are an infertility workup, assessment of uterine abnormalities, or investigation of recurrent pregnancy loss.

Two points decide whether the claim pays. First, 58340 covers both SIS and HSG catheterization under a single descriptor. Second, the imaging supervision and interpretation used to visualize the results is always a separate CPT code.

58340 CPT code description: What the code covers and excludes

Knowing the scope of 58340 prevents the two most common billing mistakes. One is unbundling work the code already includes. The other is leaving out companion codes that are legitimately billable.

What 58340 includes:

• Cervical catheter placement
• Introduction of saline (SIS) or contrast material (HSG)
• Distension of the uterine cavity or cannulation of the fallopian tubes

What 58340 does NOT include:

• Ultrasound imaging supervision and interpretation (billed separately as 76831 for SIS)
• Fluoroscopic supervision and interpretation (billed separately as 74740 for HSG)
• Diagnostic hysteroscopy or biopsy (see CPT 58558)
• Routine transvaginal ultrasound (CPT 76830), which is not an appropriate substitute for 76831 in SIS coding

The code is not limited to infertility indications. Uterine anomaly evaluation and abnormal uterine bleeding workups are equally valid clinical contexts. The supporting ICD-10 still has to match the documented indication.

CPT code pairs: 58340 with 74740 for fluoroscopic HSG and 76831 for SIS

The single most important coding decision for 58340 is selecting the correct companion imaging code. The procedure runs under two different modalities, and each has its own supervision and interpretation CPT. The wrong pairing produces a claim edit or a denial.

Substituting 76856 (complete pelvic ultrasound) for 76831 does not describe the SIS imaging protocol, so it is not an appropriate pairing with 58340. Substitutions of this kind are among the most audited errors in fertility billing. The card below sets out both pairings, plus the codes that should never stand in for them.

Sometimes a radiologist provides only the imaging interpretation while the OB/GYN performs the catheterization in a separate setting. In that split, modifier -26 applies to 74740 for the professional component. The practice billing the catheterization in its own facility reports 58340 with no modifier on the professional side.

Modifiers for CPT code 58340: When to use -26, -TC, and -59

Modifier selection for 58340 depends on who owns the equipment, who performs each component, and whether separate procedures occur on the same date of service. Incorrect modifier usage is a leading cause of audits for fertility and OB/GYN practices.

Modifier -59 carries the highest audit risk of the three. The CMS National Correct Coding Initiative (NCCI) edits govern which code pairs require separation documentation. Practices should verify current NCCI edits before applying -59 to any 58340 claim. Documentation must unambiguously support a distinct procedural service.

2026 Medicare fee schedule and reimbursement for CPT 58340

Medicare reimbursement for CPT 58340 varies by place of service and geographic locality. The figures below reflect 2026 Medicare Physician Fee Schedule (MPFS) data. Verify them with your Medicare Administrative Contractor (MAC) for your locality before using them in financial planning.

Rates also differ between facility and non-facility settings. Practice expense (PE) RVUs change based on who absorbs the overhead costs.

*Payment ranges are estimates based on publicly available 2026 MPFS data. Verify exact rates using the CMS Physician Fee Schedule lookup tool for your MAC and locality. Geographic adjustment factors (GAFs) can shift total payment significantly between high-cost urban markets and rural localities.

RVU breakdown and global period

The global period for CPT 58340 is 000 days. This means no pre-operative or post-operative services are bundled into the code. Visits on the day before and the day of the procedure can be billed separately. So can follow-up visits for complications, as long as they are documented as distinct encounters.

For practices using RVU-based compensation models, the work RVU of 1.55 reflects moderate physician effort for catheter placement and contrast introduction. Total RVU value adds wRVU, PE RVU, and malpractice RVU together. You can look that figure up in the FastRVU 2026 lookup tool, filtered by CPT 58340 and your locality.

ICD-10 diagnosis codes billed with CPT code 58340

Every 58340 claim requires a supporting ICD-10 diagnosis code that establishes medical necessity. Payers review the diagnosis to confirm the procedure is clinically appropriate for the stated indication. Infertility-related claims receive additional scrutiny because commercial payer coverage for fertility services varies widely.

Practices can cross-reference applicable diagnosis codes using the AAPC CPT-to-ICD-10 crosswalk for 58340. Our ICD-10-CM code index covers the diagnosis families that carry medical necessity for pelvic imaging. The diagnosis has to reflect the documented clinical indication in the chart. Assigning a more favorable ICD-10 to ease prior authorization is a compliance risk.

For practices managing IVF CPT codes alongside 58340, Z31.41 is frequently used for the pre-IVF fertility evaluation encounter. Confirm that the payer’s fertility policy covers diagnostic procedures under the same benefit as treatment. Some plans cover HSG and SIS separately from IVF.

CPT 58340 vs related codes: Avoiding common billing errors

Substitution errors around 58340 cluster around two problems. Coders reach for the wrong imaging companion code, or they conflate the catheterization with a diagnostic hysteroscopy. The comparison below shows the distinctions coders need to apply correctly.

The 58340 versus 58558 distinction matters most for practices that perform both procedures. CPT 58558 (hysteroscopy with biopsy) involves direct endoscopic visualization of the uterine cavity. That is a different technique from the catheterization-based approach in 58340. Billing 58558 for what was documented as an SIS or HSG is upcoding.

For practices handling insurance claims at volume, code pair rules built into the billing system keep substitution errors away from the payer. Practice management software like Pabau ships those rules inside its claims management software, which validates each claim against built-in CPT catalogs before submission. Mismatched pairs get flagged at that step, well before a denial arrives.

Payer coverage and prior authorization for CPT code 58340

Medicare covers HSG and SIS coded with 58340 when the documented indication supports medical necessity. Commercial payer coverage is considerably less consistent, particularly when the procedure is ordered for infertility evaluation.

Key payer coverage considerations:

• Prior authorization requirements: Many commercial payers require prior authorization for 58340 when the diagnosis code indicates infertility (N97.x, Z31.41). Practices in states without infertility mandate laws face the highest prior authorization burden. Always verify authorization requirements before scheduling when the indication is fertility-related.
• BCBS and regional carriers: Blue Cross Blue Shield plans vary by state. BCBS North Carolina, for example, has specific commercial coverage policies for infertility diagnostic coding that differ from their diagnostic imaging policies. Verify the applicable local policy, not the national BCBS policy.
• Non-fertility indications: Prior authorization requirements are typically lower for abnormal uterine bleeding, uterine anomaly evaluation, or recurrent pregnancy loss (N96). The procedure reads as diagnostic imaging rather than fertility treatment.
• Documentation requirements: Payers increasingly request operative notes or procedure reports for 58340 claims to confirm the service was performed as described. Practices should retain documentation of catheter placement, medium used (saline vs contrast), and the clinical indication in the chart.

Checking eligibility before the procedure date is the most reliable way to find coverage limits early. Pabau runs real-time eligibility checks through its clearinghouse connection, reading patient benefits and authorization rules against the payer’s current policy. Doing that ahead of the appointment keeps day-of-service surprises off fertility cases.

How practice management software simplifies CPT code 58340 billing

OB/GYN and fertility practices billing 58340 keep hitting the same three workflow problems.

• Code pair errors at the point of charge entry
• Modifier misapplication under time pressure
• Fee schedule updates noticed late, after reimbursement benchmarks have moved

Software built for clinical billing, rather than general scheduling, handles each of these at the system level. That takes the load off individual coder recall.

• Code pair enforcement: Billing platforms can prompt for 74740 or 76831 whenever 58340 is entered, based on the procedure type booked. That removes the manual lookup step and catches a 76830 or 76856 substitution before the claim is built.
• Modifier logic: Modifier rules set by place of service apply -26 and -TC consistently. Coders stop having to remember which setting takes which.
• Fee schedule updates: The 2026 MPFS rates are published by CMS annually. Practices using software that syncs with updated fee schedules avoid under-collection when work RVU conversions change.
• Clean claim submission: Pabau connects to Claim.MD’s clearinghouse, which covers thousands of US payers and validates CPT and ICD-10 combinations before transmission. Claims with mismatched code pairs are flagged at the validation step, well before a denial arrives.

Fertility practices code both the diagnostic side (58340) and the treatment side, including IVF and embryo transfer. One system has to carry both workflows without a manual handoff in the middle. Practices running separate billing software and EMR see claim lag and code pair errors at exactly that handoff.

The revenue effect of systematic code pair errors compounds across volume. Take a mid-size fertility practice running 20 HSG or SIS procedures a week.

Mismatching the imaging companion code puts denials on claims worth roughly $95 to $130 each at non-facility Medicare rates. Rework time and delayed cash collection sit on top of that, and both scale with the same volume.

Streamline OB/GYN and fertility billing in one platform

Pabau’s claims management software supports code pair rules, modifier logic, and fee schedule updates so your team submits cleaner 58340 claims from the start.

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Conclusion

Coding 58340 well comes down to one decision, made the same way every time. Match the companion imaging code to the modality used, then support the claim with a diagnosis the chart already documents.

Coder recall alone does not hold up at volume, so the rule belongs in the system rather than in someone’s memory. Set the code pair and modifier logic once and every 58340 claim inherits it. Book a demo to see how Pabau keeps fertility and OB/GYN claims clean before they reach the payer.

Continue your research

Managing IVF billing alongside HSG claims? IVF CPT codes covers the full ART procedure code set for fertility practices billing both diagnostic and treatment services.

Need to verify eligibility before fertility appointments? Insurance eligibility verification explains how real-time checks surface prior authorization requirements before the patient arrives.

Want fewer edits on your 58340 claims? What is a clean claim in medical billing? walks through the validation steps that catch code pair errors before submission.

Already working a denial queue? Denial management in healthcare sets out the process for reworking denials and stopping the same edit from repeating.

Frequently asked questions