Modifier TH: Obstetrical Treatment, Prenatal or Postpartum
Modifier TH identifies obstetrical treatment or services, prenatal or postpartum. Used to flag maternity care on E/M claims, mainly for Medicaid.
When to Append Modifier TH
Append TH to an evaluation and management code to identify the encounter as prenatal or postpartum maternity care rather than a general visit.
- Omitting TH on component-billed maternity visits for a payer that requires it, which causes the visit to be adjudicated as general care.
Source: HCPCS Level II official descriptor
Modifier TH in Detail
Modifier TH identifies a service as obstetrical treatment, either prenatal or postpartum. It is appended to evaluation and management codes so the payer can distinguish maternity care from a general office visit when the visit is billed separately rather than inside a global obstetric package.
It matters most in Medicaid billing, where several state programmes require TH on antepartum visits, deliveries and postpartum care in order to track maternity services and apply the correct payment rules. This is closely tied to OB/GYN billing and to Florida Medicaid requirements. Obstetric claims are worked inside OB/GYN billing, and the full set is listed in the billing modifiers library. Modifier use is a compliance matter as much as a billing one, covered in medical billing compliance.
Using Modifier TH Correctly
When to Apply
Apply this modifier only when the clinical circumstances described in the modifier definition are present and documented in the medical record.
Procedure Code Compatibility
Confirm this modifier is applicable to the procedure codes being billed. Not all modifiers are valid with all CPT codes.
Documentation Support
Ensure the medical record supports the modifier's use. Auditors will review documentation to confirm the modifier is appropriate.
Payer Acceptance
Verify that the payer accepts this modifier and understand how it affects reimbursement before submitting the claim.
Modifier TH Reference
| Field | Details |
|---|---|
| Modifier | TH |
| Official Description | Obstetrical treatment/services, prenatal or postpartum. |
| When to Use | Append TH to an evaluation and management code to identify the encounter as prenatal or postpartum maternity care rather than a general visit. |
| Where It Applies Most | State Medicaid programmes commonly require TH on antepartum visits, deliveries and postpartum care so maternity services can be identified and paid under the correct policy. |
| Global Package Interaction | When obstetric care is billed as a global package the individual visits are not separately reported. TH applies where care is billed by component, such as when a patient transfers care mid-pregnancy. |
| Payer Variation | Requirements differ by payer and by state programme. Confirm whether the plan requires TH before submitting, since applying it where it is not recognised can trigger a rejection. |
| Common Error | Omitting TH on component-billed maternity visits for a payer that requires it, which causes the visit to be adjudicated as general care. |
Source: HCPCS Level II official descriptor
Related Billing Resources
Modifier TH, Frequently Asked Questions
Obstetrical treatment/services, prenatal or postpartum.
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