Modifier TH — Obstetrical treatment/services
Defines when Premera recognizes modifier TH appended to E&M office or home/residence visit codes to indicate antepartum visits 1-3 and how billing should be handled for additional antepartum or global maternity care; applies to Premera Blue Cross and affiliated lines of business (excludes Alaska providers).
No material clinical or coverage changes in this revision.
Modifier TH Coverage Criteria
Modifier TH coverage criteria
Covered when ALL of the following are met:
ALL of the following
- Modifier TH is appended only for antepartum visits 1-3; it is not appended to any postpartum E&M visit code (e.g., 59430 is a separate postpartum procedure code).
Applicable Codes
Billing Actions for Modifier TH
Billing: Append modifier TH only for antepartum visits 1–3
Append modifier TH only to an E&M office visit (CPT 99202–99215) or a home/residence visit (CPT 99341–99350) to indicate antepartum visits 1–3. Do not append TH to any postpartum E&M visit. If the same provider renders more than three antepartum visits, submit the appropriate antepartum visit code (59425 or 59426) or a global maternity care code (59400, 59510, 59610, 59618) when complete maternity care is provided. An E&M visit with modifier TH must not be billed by the same provider or provider group that bills a global maternity care code for the same patient.
- Modifier TH applies only to antepartum visits 1–3 on E&M office (99202–99215) or home/residence (99341–99350) visit codes.
- Do not append TH to postpartum E&M visits (59430 is a separate postpartum code).
- For >3 antepartum visits by the same provider: bill 59425 (4–6 visits) or 59426 (7+ visits) or a global maternity code (59400, 59510, 59610, 59618).
- The provider billing TH must not be the same provider/group that bills the global maternity care code.
Key Definitions
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