What Is Changing in Maternity Care Coding for 2027?
Beginning January 1, 2027, the AMA CPT Editorial Panel is retiring the global obstetric billing codes that OB/GYN practices have used for over 30 years and replacing them with a phase-based coding structure that reports antepartum care, labor management, delivery, and postpartum services as separate codes. The change involves 35 code modifications: 17 codes deleted, 12 new codes added, and 6 codes revised. CMS is currently deciding whether to adopt the new CPT codes or create parallel HCPCS G-codes that preserve the old structure for Medicare.
What is being deleted: The global obstetric codes including 59400 (vaginal delivery total), 59510 (cesarean total), and 59610 (VBAC total) are being retired along with 14 other codes.
What replaces them: Four separate phases of care, each with its own codes: antepartum E/M visits, labor management, delivery, and postpartum. Practices will bill each phase individually instead of one bundled global code.
CMS decision pending: CMS has proposed either adopting the new CPT codes or creating parallel G-codes. ACOG opposes the G-code option. The comment period closes September 14, 2026, and the final rule is expected this fall.
Why the Global Codes Are Being Retired
The current global obstetric codes, 59400, 59510, 59610, and 59618, bundle antepartum care, delivery, and postpartum care into a single payment. They have been in place since the mid-1990s with only minor adjustments in 2009. The AMA and ACOG determined that these bundled codes no longer reflect how maternity care is actually delivered. Pregnancy care now routinely involves multiple care teams, transfers between facilities, telehealth visits, and varied numbers of antepartum encounters that the global structure cannot capture.
Under the current system, the global code is billed when the baby is delivered, regardless of how many providers were involved in the pregnancy. That creates attribution problems: only the delivering physician can bill the global code, which leaves antepartum work by other providers unreported or undervalued. In our experience matching OB/GYN practices with billing partners, the global code also makes it difficult for practices to track revenue by phase of care, because all of the work collapses into a single line item at delivery.
The new structure separates maternity care into four reportable phases: antepartum care (reported with standard E/M codes for each prenatal visit), labor management (new codes), delivery (revised codes), and postpartum care (new codes). This means every provider who contributes to a pregnancy can bill for their specific phase of involvement, and the practice can see exactly where revenue is generated and where it leaks.
What Codes Are Changing?
The restructuring involves 35 total code modifications. The table below shows the most significant deletions and their replacements.
| Current code | Description | Replaced by | Status in 2027 |
|---|---|---|---|
| 59400 | Vaginal delivery (total OB care) | Phase-based codes for antepartum + delivery + postpartum | Deleted |
| 59510 | Cesarean delivery (total OB care) | Phase-based codes for antepartum + delivery + postpartum | Deleted |
| 59610 | VBAC (total OB care) | Phase-based codes for antepartum + delivery + postpartum | Deleted |
| 59618 | Cesarean after failed VBAC (total) | Phase-based codes for antepartum + delivery + postpartum | Deleted |
| 59425/59426 | Antepartum care (4-6 / 7+ visits) | Individual E/M codes per prenatal visit | Deleted |
The AMA published the new codes and guidelines early to give practices time to prepare. The CPT 2027 Professional Edition, expected later in 2026, will contain the final descriptor language.
What Is CMS Proposing for Medicare?
In the CY 2027 PFS proposed rule (CMS-1848-P), published July 16, 2026, CMS proposed two options for handling the maternity code restructuring under Medicare. The first option adopts the new CPT codes with slight modifications to the AMA’s recommended valuations, adjusting the number of bundled E/M visits from 12 to 8 for average-risk pregnancies. The second option creates 15 new HCPCS G-codes that would retain the current global code structure specifically for Medicare, even as commercial payers and Medicaid programs adopt the new CPT codes.
ACOG and the OB Hospitalist Group have publicly opposed the G-code option, arguing that maintaining a parallel coding system for Medicare would create confusion, increase administrative burden, and undermine the purpose of the restructuring. The comment period closes September 14, 2026, and the final rule is expected in November.
One question we hear constantly from practice managers is whether this change will reduce total maternity reimbursement. CMS and the AMA have both stated that the restructuring is intended to be budget neutral. However, how revenue distributes across the four phases of care will change, and practices that currently bill only the global code at delivery will see their payment timeline shift to multiple smaller payments throughout the pregnancy.
The maternity code overhaul is the biggest change to OB/GYN billing in 30 years. If your practice bills global obstetric codes today, your billing system, EHR templates, and charge capture workflow will all need to change before January 2027. A billing partner with OB/GYN experience can map your current global code volume to the new phase-based structure and model the revenue shift. Get matched with vetted OB/GYN billing companies, free.
What Should OB/GYN Practices Do Now?
The January 2027 effective date is four months away. These are the preparation steps that protect revenue through the transition.
Pull your global code volume. Count how many 59400, 59510, 59610, and 59618 claims your practice billed over the past 12 months. This is your baseline for modeling how revenue will redistribute across the new phase-based codes.
Map your antepartum visit count. Under the new structure, each prenatal visit is reported individually with E/M codes instead of bundled into the global code. Knowing your average visits per pregnancy tells you how many more claims you will submit per patient.
Confirm your EHR vendor’s timeline. Your EHR needs updated templates, charge capture screens, and order sets that reflect the four-phase structure. Contact your vendor now to confirm when the 2027 maternity code update will be available.
Watch the CMS final rule. If CMS creates parallel G-codes for Medicare, your practice will need to use one code set for Medicare patients and a different one for commercial and Medicaid patients. That doubles the workflow complexity.
Train your coding and billing staff. The transition from global to phase-based billing changes when claims are submitted, how many claims per pregnancy are generated, and how payment timing works. Staff who have billed the global code for years will need retraining before January.
Review your payer contracts. Commercial payers and state Medicaid programs each decide independently whether to adopt the new CPT codes. Confirm with your top payers whether they plan to accept the new codes on January 1 or will follow a different timeline.
Mistakes Practices Will Make on This Transition
Across the billing companies we vet, the same errors appear every time a major code set changes.
Billing the retired global code after January 1. If 59400, 59510, 59610, or 59618 is submitted for a date of service on or after January 1, 2027, the claim will be rejected. Practices that do not update their charge capture before the cutover will generate automatic denials on every delivery.
Forgetting to bill antepartum visits individually. Under the global code, prenatal visits were bundled and not separately reported. Under the new structure, each visit is an individual E/M claim. Practices that do not start billing these visits separately will leave antepartum revenue on the table.
Assuming the transition is budget neutral at the practice level. CMS intends budget neutrality at the national level, but individual practices may see revenue shifts depending on their delivery volume, average visit count, and payer mix. High-volume delivery practices may see different effects than practices with heavy antepartum panels.
Waiting for the final rule. The CPT code changes take effect January 1 regardless of what CMS decides about G-codes. Commercial payers will adopt the new CPT codes. Only the Medicare side is uncertain.
Frequently Asked Questions
Are the global obstetric codes being deleted?
Yes. CPT codes 59400, 59510, 59610, 59618, 59425, 59426, and 11 other maternity codes are being deleted effective January 1, 2027. They are replaced by phase-based codes for antepartum, labor management, delivery, and postpartum services.
Will this reduce maternity reimbursement?
CMS and the AMA intend the restructuring to be budget neutral at the national level. However, how revenue distributes across the four phases of care will change, and individual practices may see shifts depending on their delivery volume and payer mix.
What happens if CMS creates G-codes instead of adopting CPT?
If CMS finalizes the G-code option, Medicare claims would use the new HCPCS G-codes that mirror the current global structure, while commercial payers use the new CPT codes. OB/GYN practices would need to manage two parallel code sets. ACOG opposes this approach.
When does the CMS comment period close?
September 14, 2026. ACOG and other OB/GYN organizations are encouraging providers to submit comments opposing the G-code option and supporting adoption of the new CPT maternity codes.
Can I still bill 59400 for a delivery in January 2027?
No. If the CPT code 59400 is deleted as planned, submitting it for a date of service on or after January 1, 2027 will result in a claim rejection. Your practice must transition to the new phase-based codes before that date.
How many more claims will my practice submit per pregnancy?
Under the current system, most of the maternity billing collapses into one global code billed at delivery. Under the new system, each antepartum visit, labor management service, delivery, and postpartum visit is reported individually. A typical pregnancy will generate significantly more individual claims, which requires more billing workflow capacity.
The global obstetric codes your practice has billed for decades are being retired in four months. Whether you need a billing partner who can map your current global code volume to the new phase-based structure, train your staff on the transition, or manage the dual-code complexity if CMS creates G-codes, OB/GYN Bill Co connects you with vetted billing companies at no cost. More than 2,000 providers matched, all 50 states, over 15 years in medical billing, rates from 2.95 percent. Matching is 100 percent free.
