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Changes to Global Maternity Care and Delivery Coding
Blue Cross Blue Shield of Vermont·VT · OB-GYN·Coding
Effective date
Sep 1, 2026
We identified it
Aug 4, 2026
Summary
Effective September 1, 2026, maternity care billing transitions from global codes to phase-based E/M codes with modifier -TH and pregnancy diagnosis codes. Current global antepartum codes (59425, 59426) will be replaced by individual E/M codes for prenatal visits. A complete transition to granular four-phase coding (antepartum, labor management, delivery, postpartum) occurs January 1, 2027.
Action Required
By August 31, 2026: Billing team must update billing software and encounter forms to transition maternity coding. IMMEDIATE ACTIONS REQUIRED: (1) Coding team: Stop using global antepartum codes 59425 and 59426 for dates of service on or after 9/1/2026. (2) Billing system: Configure to require modifier -TH on all E/M codes for maternity prenatal visits after 9/1/2026. (3) Clinical documentation: Update EMR templates to ensure providers document ICD-10 Z34.XX (pregnancy gestation) or O00-O9A diagnosis codes on all prenatal visit notes. (4) Providers and coders: Train on new E/M coding rules requiring documentation of medical decision making (MDM) or time per CPT guidelines. (5) For dates of service 9/1/2026 through 12/31/2026: Bill prenatal visits using appropriate E/M code + modifier -TH + Z34.XX or O00-O9A codes. (6) Before January 1, 2027: Prepare for phase-based coding system replacement. Failure to implement will result in claim denials and revenue loss. Reference AMA CPT 2027 Maternity Care Services guidelines for complete specifications.