RetiredPremera BluecrossPolicy N/A

Modifier TH - Obstetrical treatment/services

Defines when Premera recognizes modifier TH appended to professional E&M or home/residence visit codes to indicate antepartum visits 1-3, and describes billing interactions with antepartum and global maternity codes; applies to Premera lines of business except Alaska.

Policy Summary

PayerPremera Bluecross

PolicyModifier TH - Obstetrical treatment/services

Policy CodePolicy N/A

Change TypeArchived

Effective DateN/A

Next Review DateN/A

Key ActionAppend modifier TH to E&M office visit (99202-99215) or home/residence visit (99341-99350) to indicate antepartum visits 1-3; do not append for postpartum visits and avoid billing TH when the same provider bills a global maternity code.

SourceLink

POLICY UPDATE CHANGES

This policy is archived effective April 2, 2026 and users are directed to the Maternity Services policy for related information.

antepartum 1-3use of modifier TH allowed for these visits

4+ visitsrequires antepartum codes or global code for 4+ visits

AlaskaAlaska exception

04/02/26policy archive date

03/12/26last review

Modifier TH Coverage Criteria

Modifier TH coverage criteria

Coverage and billing criteria for modifier TH and related obstetrical visit codes:

Modifier TH is recognized when appended to E&M office visit codes (99202-99215) or home/residence visit codes (99341-99350) to indicate antepartum visits 1-3.

Modifier TH must not be appended to postpartum E&M visit codes.

If a provider delivers more than three antepartum visits, bill appropriate antepartum visit codes (59425 for 4-6 visits or 59426 for 7 or more visits) or bill an appropriate global maternity code (59400, 59510, 59610, 59618) when complete maternity care is rendered.

An E&M or home/residence visit code appended with modifier TH should not be billed by the same provider or provider group that bills a global maternity care code (59400, 59510, 59610, 59618) for the same patient.

Policy Summary

PayerPremera Bluecross

PolicyModifier TH - Obstetrical treatment/services

Policy CodePolicy N/A

Change TypeArchived

Effective DateN/A

Next Review DateN/A

SourceLink

On This Page

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Referenced CPT and Visit Code Details

Referenced CPT codesCPT

99202-99205	New patient office visits (E&M) — see policy for time/MDM requirements
99211-99215	Established patient office visits (E&M) — see policy for time/MDM requirements
99341-99345	New patient home or residence visits — see policy for time requirements
99347-99350	Established patient home or residence visits — see policy for time requirements
59425	Antepartum care only; 4-6 visits
59426	Antepartum care only; 7 or more visits
59430	Postpartum care only
59400, 59510, 59610, 59618	Global obstetrical care codes (routine obstetric care including antepartum, delivery and postpartum)

Time / MDM thresholds for E&M and home/residence visits

New patient office visit time thresholds (99202-99205)99202 = 15 minutes; 99203 = 30 minutes; 99204 = 45 minutes; 99205 = 60 minutes (time-based selection)

Established patient office visit time thresholds (99211-99215)99211 = (may not require physician); 99212 = 10 minutes; 99213 = 20 minutes; 99214 = 30 minutes; 99215 = 40 minutes (time-based selection)

New patient home/residence visit time thresholds (99341-99345)99341 = 15 minutes; 99342 = 30 minutes; 99344 = 60 minutes; 99345 = 75 minutes (total time on date of encounter)

Established patient home/residence visit time thresholds (99347-99350)99347 = 20 minutes; 99348 = 30 minutes; 99349 = 40 minutes; 99350 = 60 minutes (total time on date of encounter)

Billing and Documentation Guidance

Billing Rule

Append modifier TH for antepartum visits 1-3; billing interactions with antepartum/global maternity codes

Append modifier TH to an E&M office visit (99202-99215) or a home/residence visit (99341-99350) to indicate antepartum visits 1-3. Do not append TH to postpartum E&M visit codes. Do not bill an E&M or home/residence visit code with modifier TH by the same provider or provider group that bills a global maternity care code (59400, 59510, 59610, 59618). For four or more antepartum visits by the same provider, bill antepartum visit codes (59425 for 4-6 visits or 59426 for 7+ visits) or an appropriate global maternity code when complete maternity care is rendered.

Modifier TH is accepted only for antepartum visits 1-3 on professional claims.
Do not append TH to postpartum E&M visit codes.
If ≥4 antepartum visits, submit 59425 (4-6 visits) or 59426 (7+ visits) or an appropriate global maternity code (59400, 59510, 59610, 59618).
An E&M/home visit with TH must not be billed by the same provider/provider group that bills a global maternity code for the same patient.

Key Terms and Code Groupings

Modifier TH — definition and usage

DefinitionModifier TH = Obstetrical treatment/services modifier appended to an E&M office visit (99202-99215) or a home/residence visit (99341-99350) to indicate antepartum visits 1-3.

Not for postpartumModifier TH must NOT be appended to postpartum E&M visit codes.

Provider/group billing restrictionAn E&M or home/residence visit code appended with modifier TH should not be billed by the same provider or provider group that bills a global maternity care code.

Antepartum and global maternity codes

Antepartum-only codes59425 = Antepartum care only; 4-6 visits; 59426 = Antepartum care only; 7 or more visits.

Postpartum-only code59430 = Postpartum care only (separate procedure).

Global obstetrical care codes59400, 59510, 59610, 59618 = Routine obstetric care including antepartum care, delivery (vaginal or cesarean as indicated) and postpartum care.