Direct answer: OB/GYN billing and coding requires accurate maternity-package billing, trimester-specific diagnosis coding, proper modifier use, and clear documentation. Practices must also distinguish routine prenatal care from separately billable complications, procedures, preventive services, and unrelated medical care.
Last reviewed: August 2026. This article provides general billing information and does not replace current coding manuals, payer policies, or professional advice.
Stop Losing Money on Rejected Claims
Schedule a free review call today - we’ll show you how to eliminate errors and speed up approvals.
What Is OB/GYN Billing and Coding?
OB/GYN billing and coding converts obstetric and gynecologic services into standardized insurance claims. These claims may include prenatal care, delivery, postpartum care, preventive visits, diagnostic testing, and surgical procedures.
However, OB/GYN billing differs from many other specialties. A single practice may manage routine maternity care, high-risk pregnancies, preventive examinations, imaging, contraception, and major surgery.
Therefore, billing staff must identify which services belong to a package and which services qualify for separate reporting.
Why OB/GYN Billing Is Complex
Several factors make OB/GYN revenue cycle management challenging:
- Global maternity packages combine several services into one payment.
- Many obstetric diagnoses require trimester information.
- Pregnancy-related conditions often affect code sequencing.
- Payers apply different maternity and preventive-care rules.
- Ultrasounds and procedures require medical-necessity documentation.
- Modifiers must accurately explain separately reportable services.
- Coverage may change during a pregnancy.
- Providers may transfer care before delivery.
As a result, practices need a consistent process from registration through denial follow-up.
Verify Insurance Before Providing Care
Eligibility verification should begin at the first appointment. Staff should confirm:
- Active coverage on the date of service
- Maternity benefits
- Preventive-service benefits
- Deductible, copayment, and coinsurance amounts
- Referral and authorization requirements
- Network status for the provider and facility
- Coverage for ultrasounds and genetic testing
- Hospital and delivery benefits
- Newborn enrollment requirements
- Coordination-of-benefits rules
Next, document the verification result in the patient’s account. Staff should also recheck coverage during the pregnancy because insurance may change before delivery.
Nevertheless, verification does not guarantee payment. The payer makes its final decision after processing the claim.
Understanding the Global Obstetric Package
The global obstetric package combines routine antepartum care, delivery, and postpartum care. The provider reports one global code when the same practice supplies all required components.
Common global maternity codes include:
| Code | General Service |
|---|---|
| 59400 | Routine maternity care with vaginal delivery |
| 59510 | Routine maternity care with cesarean delivery |
| 59610 | Routine maternity care with vaginal delivery after a previous cesarean delivery |
| 59618 | Routine maternity care with cesarean delivery after a previous cesarean delivery |
Always confirm the complete code requirements before submission. In addition, review the patient’s payer contract because maternity billing policies can differ.
Services Usually Included in Global Maternity Care
The global package generally includes routine services related to the pregnancy. Examples may include:
- Routine prenatal visits
- Routine monitoring of the pregnancy
- Management of labor
- The delivery service
- Routine postpartum care
CMS NCCI guidance also includes certain services within delivery codes. For example, fetal monitoring during labor, an episiotomy, and delivery of the placenta may already form part of the reported delivery service.
Therefore, do not unbundle routine components merely because a separate code exists.
Services That May Fall Outside the Global Package
Some services may qualify for separate reporting when the documentation and payer policy support them. Examples may include:
- Treatment of a significant pregnancy complication
- Care for an unrelated medical condition
- Medically necessary diagnostic testing
- Certain procedures that the global package does not include
- Services provided before the global maternity period begins
- Care after the patient transfers to another provider
Do not assume that every additional service qualifies for separate payment. Instead, compare the service with the current coding guidelines and the payer’s maternity policy.
Billing Partial Maternity Care
A practice may not provide every component of maternity care. For example, the patient may transfer care, change insurance, move to another location, or deliver with a different group.
In these cases, the practice may need to report the individual services it performed.
| Code | General Use |
|---|---|
| 59425 | Antepartum care involving four to six visits |
| 59426 | Antepartum care involving seven or more visits |
| 59409 | Vaginal delivery only |
| 59410 | Vaginal delivery with postpartum care |
| 59514 | Cesarean delivery only |
| 59515 | Cesarean delivery with postpartum care |
When the practice provides fewer than four antepartum visits, it may report the appropriate office E/M services instead. However, payer rules may vary.
Keep a clear record of the number of visits, transfer date, delivery provider, and services performed.
ICD-10-CM Coding for Pregnancy
Most obstetric diagnoses appear in Chapter 15 of ICD-10-CM. These codes cover pregnancy, childbirth, and the puerperium.
Many obstetric codes require trimester information. Therefore, the provider should document the trimester and weeks of gestation at each encounter.
Trimester Documentation
Coders should not calculate the trimester from incomplete information. Instead, they should use the provider’s documentation and official ICD-10-CM definitions.
When appropriate, add a code from category Z3A to report the completed weeks of gestation.
Normal Pregnancy Supervision
Codes from category Z34 may describe supervision of a normal pregnancy. However, do not use a normal-pregnancy supervision code when the provider manages a current pregnancy complication that requires an obstetric diagnosis.
High-Risk Pregnancy Supervision
High-risk pregnancy codes require documentation of the reason for increased supervision. The record should explain the condition, history, or risk that affects the pregnancy.
Pregnancy-Related Complications
Use the most specific obstetric diagnosis supported by the record. In addition, report any secondary code needed to describe the underlying condition.
Follow the official sequencing instructions because obstetric codes often take priority over codes from other ICD-10-CM chapters.
Preventive Gynecology Visits
A preventive gynecology visit evaluates the patient’s general health and preventive-care needs. The provider may review history, perform an age-appropriate examination, discuss risk reduction, and recommend screenings.
Preventive medicine codes depend on the patient’s age and whether the patient is new or established.
| Code Group | General Purpose |
|---|---|
| 99384–99387 | Preventive services for new patients, selected by age |
| 99394–99397 | Preventive services for established patients, selected by age |
Diagnosis code Z01.419 may apply to a gynecological examination without abnormal findings. Conversely, Z01.411 may apply when the examination identifies abnormal findings.
Always confirm that the diagnosis matches the medical record.
Problem-Oriented Care During a Preventive Visit
A provider may address a significant medical problem during a preventive examination. Examples include abnormal bleeding, pelvic pain, infection, or medication management.
The practice may report a separate problem-oriented E/M service when the provider performs and documents work beyond the preventive service.
Modifier 25 may apply to the problem-oriented E/M code. However, the record must clearly show the separately identifiable evaluation and management work.
Do not use modifier 25 merely because the provider documented an additional diagnosis.
Medicare Screening Services
Medicare applies specific rules to cervical or vaginal cancer screening services. Depending on coverage and documentation, codes may include:
- G0101: Screening pelvic examination and clinical breast examination
- Q0091: Collection of a screening Pap smear specimen
Coverage depends on eligibility, frequency, risk factors, and the reason for the service. Therefore, verify Medicare requirements before billing.
Do not automatically substitute these codes for every gynecological visit. The patient may also receive medically necessary problem-oriented care that requires separate documentation.
Ultrasound Billing in OB/GYN
Ultrasound billing requires a valid order, medical necessity, complete findings, and a signed interpretation. The selected code must match the type and purpose of the study.
Documentation should identify:
- The clinical indication
- The pregnancy status and gestational age when relevant
- The ultrasound approach
- The structures evaluated
- The measurements and findings
- The provider’s interpretation
- The effect on the treatment plan
In addition, review payer frequency limits and NCCI edits. Repeated ultrasounds need documentation that explains why the provider required another study.
Professional and Technical Components
Some diagnostic services include both professional and technical work. The professional component covers the provider’s interpretation. The technical component covers equipment, supplies, and technical staff.
Modifier 26 may identify the professional component. Meanwhile, modifier TC may identify the technical component.
Do not use these modifiers unless the service and payer permit component billing. Also confirm which entity performed and documented each component.
Common OB/GYN Modifiers
| Modifier | General Purpose |
|---|---|
| 24 | Unrelated E/M service during a postoperative period |
| 25 | Significant and separately identifiable E/M service on the same day as another service |
| 26 | Professional component |
| TC | Technical component |
| 57 | E/M service that results in the decision for major surgery |
| 59 | Distinct non-E/M procedural service when documentation supports it |
| 78 | Related return to an operating or procedure room during the postoperative period |
| 79 | Unrelated procedure during the postoperative period |
Use each modifier only when the circumstances meet its official definition. Also check whether the payer requires a more specific modifier.
Read our medical billing modifier guide for additional guidance.
Modifier 25 in OB/GYN Billing
Modifier 25 commonly causes confusion. It does not make an included service separately payable by itself.
The documentation should show:
- A significant problem that required additional evaluation
- Work beyond the preventive visit or procedure
- A separate assessment
- A clear treatment or management plan
- The medical necessity for the additional E/M service
The E/M service may relate to the same diagnosis as the procedure. Nevertheless, the documented work must remain significant and separate.
Modifier 59 and NCCI Edits
CMS uses NCCI edits to prevent improper payment for services that should not normally appear together.
Modifier 59 may identify separate non-E/M procedures under limited circumstances. For example, documentation may support services performed during separate encounters or at separate anatomical sites.
Never append modifier 59 simply to override a denial. First, confirm that the edit allows a modifier and that the record supports the distinction.
Common Gynecologic Procedures
OB/GYN practices perform many office and surgical procedures. Examples include:
- Colposcopy
- Cervical or endometrial biopsy
- Hysteroscopy
- Intrauterine device insertion or removal
- Contraceptive implant insertion or removal
- Loop electrosurgical excision procedures
- Hysterectomy
- Sterilization procedures
Each procedure requires accurate documentation. The record should identify the indication, technique, findings, specimens, complications, and follow-up plan.
Furthermore, confirm authorization requirements and medical-necessity policies before performing scheduled procedures.
Contraceptive Device Billing
Contraceptive services may involve the device, insertion or removal, and a separately identifiable E/M service. However, payer policies vary widely.
Before the appointment, verify:
- Coverage for the selected device
- Pharmacy or medical benefit requirements
- Prior authorization
- Device acquisition rules
- Patient cost-sharing
- Replacement frequency
After the procedure, record the device details, lot number, expiration date, insertion or removal technique, and patient instructions.
Documentation for Surgical Procedures
The operative note should support every reported procedure. Include:
- The preoperative and postoperative diagnoses
- The reason for the procedure
- The exact procedure performed
- The surgical approach
- Relevant findings
- Specimens collected
- Complications
- Estimated blood loss when relevant
- The postoperative plan
Do not choose a code from the scheduled procedure alone. Instead, code the procedure that the provider actually performed and documented.
Common OB/GYN Claim Denials
1. Service Included in the Maternity Package
The payer may deny a service because it considers the work part of global maternity care. Review the documentation and the payer’s package definition before appealing.
2. Missing or Incorrect Trimester
An obstetric diagnosis may deny when the trimester conflicts with the gestational age. Confirm both elements before claim submission.
3. Modifier 25 Not Supported
A separate E/M service may deny when the record only documents routine work associated with the preventive visit or procedure.
4. Ultrasound Medical Necessity Missing
The diagnosis, order, and interpretation must support the ultrasound. Routine repetition without a documented reason may trigger a denial.
5. Authorization Missing
Some plans require authorization for imaging, genetic testing, surgery, sterilization, and contraceptive devices. Confirm approval before treatment.
6. Coverage Changed During Pregnancy
A patient may change insurance before delivery. Reverify coverage regularly and determine how each payer handles the maternity claim.
7. Provider Enrollment Error
A payer may deny the claim when the provider or location does not match its enrollment records. Keep credentialing information current.
8. Duplicate Claim
Do not resubmit an unpaid claim before checking its status. A second submission may create a duplicate denial and delay resolution.
OB/GYN Claim Review Checklist
- Verify eligibility and maternity benefits.
- Confirm the provider and facility network status.
- Identify whether global or partial maternity billing applies.
- Count and document antepartum visits.
- Confirm the delivery and postpartum providers.
- Check trimester and gestational-age documentation.
- Review diagnosis sequencing.
- Confirm authorization requirements.
- Review NCCI edits before reporting multiple procedures.
- Use modifiers only when documentation supports them.
- Check ultrasound orders and interpretations.
- Submit the claim before the payer’s filing deadline.
Improving the OB/GYN Revenue Cycle
A reliable revenue cycle begins with accurate registration and eligibility verification. Next, the practice should review documentation and charges before claim submission.
Practices should also track:
- Claim rejection reasons
- Denial categories
- Accounts-receivable aging
- Unbilled maternity claims
- Authorization failures
- Underpayments
- Patient balances
- Credentialing deadlines
Finally, review repeated denials with clinical and billing staff. A targeted workflow change can prevent the same error from affecting future claims.
How Professional OB/GYN Billing Support Can Help
OB/GYN practices must manage maternity packages, gynecologic procedures, preventive services, imaging, and payer-specific rules. A specialized billing team can help coordinate these responsibilities.
Professional support may include:
- Eligibility and benefit verification
- Authorization tracking
- Charge and coding review
- Global maternity claim management
- Claim submission and rejection correction
- Payment posting
- Denial analysis and appeals
- Accounts-receivable follow-up
- Credentialing support
Learn more about our medical billing and coding services, or contact our team to discuss OB/GYN revenue cycle support.
Frequently Asked Questions
What does a global maternity package include?
It generally includes routine antepartum care, delivery, and routine postpartum care. The exact components and billing rules depend on the code and payer.
Can a practice bill a separate visit during global maternity care?
Sometimes. The service must fall outside routine maternity care, and the documentation must support separate reporting under the payer’s rules.
When should an OB/GYN practice use modifier 25?
Use modifier 25 on an E/M code when the provider performs a significant and separately identifiable E/M service on the same day as another service or procedure.
What happens when a patient transfers maternity care?
The providers may need to report antepartum, delivery, and postpartum services separately. Document the transfer date and services each provider performed.
Why do obstetric claims deny for trimester errors?
The diagnosis may conflict with the documented gestational age, or the claim may lack required trimester information. Review both before submission.
How can an OB/GYN practice reduce denials?
Verify benefits, track maternity services, document trimester information, obtain authorizations, review modifiers, and correct rejected claims promptly.
