OBSTETRICS & GYNECOLOGY MEDICAL CODING GUIDE
Comprehensive Obstetrics & Gynecology Medical
Coding Guide
Table of Contents
1. Foundations & E/M Coding in OB/GYN
2. Gynecology: Office & Inpatient Procedures
o Preventive Medicine
o Vulvar, Vaginal, Cervical Procedures
o Uterine & Endometrial Procedures
o Laparoscopic & Open Surgeries
o Pelvic Floor & Urogynecology
3. Obstetrics: The Global Package & Beyond
o Antepartum, Delivery, Postpartum
o High-Risk Obstetrics
o Ultrasound & Fetal Testing
4. ICD-10-CM Deep Dive
o 7th Character Specifics (Fetus, Trimester, Episode of Care)
o Complication Codes (O00–O9A)
o Z Codes for Supervision
5. Modifiers in Depth
6. Payer-Specific Rules (Medicare, Medicaid, Commercial)
7. Denial Prevention & Audit Checklists
8. Clinical Scenarios with Full Coding Pathways
Section 1: Foundations & E/M Coding
Evaluation & Management (E/M) Guidelines for 2024–2025
OB/GYN uses the Medical Decision Making (MDM) or Time methodology for office/outpatient
visits (99202–99215). Inpatient visits (99221–99233) use time or MDM as well.
Key OB/GYN E/M Codes
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, OBSTETRICS & GYNECOLOGY MEDICAL CODING GUIDE
Setting Code Range Typical Use
Office New Patient 99202–99205 First OB intake, new GYN consult
Office Established 99212–99215 Follow-up visits, postoperative checks
Inpatient Initial 99221–99223 Admission for preterm labor, postpartum complicat
Inpatient Subsequent 99231–99233 Daily rounding on hospitalized OB/GYN patient
Observation 99218–99220 Rule-out ectopic, hyperemesis, preterm labor moni
Consultations 99242–99245 (outpatient) Rarely used by commercial; Medicare no longer rec
Time vs. MDM in OB/GYN
• Time-based: Includes total time on date of encounter (prep, chart review, counseling,
care coordination). Document total time and what was done.
• MDM-based: Based on problems, data, risk. Example: A patient with abnormal
bleeding (moderate risk) + labs + prescription = Level 3 or 4.
Example Documentation:
"Total time spent with patient and family today was 45 minutes. I reviewed outside records,
performed a pelvic exam, counseled on endometriosis treatment options including hormonal
therapy and surgery, and coordinated referral to reproductive endocrinology." → 99205 (new
patient) or 99215 (established).
Section 2: Gynecology – Detailed Coding
2.1 Preventive Medicine (Annual Exams)
Patient Status Age Code
New patient Under 1 year 99381
New patient 1–4 99382
New patient 5–11 99383
New patient 12–17 99384
New patient 18–39 99385
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, OBSTETRICS & GYNECOLOGY MEDICAL CODING GUIDE
Patient Status Age Code
New patient 40–64 99386
New patient 65+ 99387
Established Under 1 year 99391
Established 1–4 99392
Established 5–11 99393
Established 12–17 99394
Established 18–39 99395
Established 40–64 99396
Established 65+ 99397
HCPCS for Medicare/Medicaid:
• G0101 – Cervical/vaginal cancer screening (Pap) – frequency per payer
• Q0091 – Screening Pap smear collection (often billed with G0101)
Modifier -25: Append when a problem is addressed during an annual exam (e.g., UTI, vaginitis,
breast lump). Bill preventive code + E/M code (e.g., 99395 + 99213-25).
2.2 Vulvar & Vaginal Procedures
Procedure CPT Details & Notes
Vulvar biopsy (single) 56605 Includes local anesthesia
Vulvar biopsy (each add'l) +56606 Use modifier -51 or -59 as required
Vulvar vestibulectomy 56620 Complete; for vestibulodynia
Vaginal biopsy 57100 Simple, single site
Vaginectomy (partial) 57106 Includes mucosa resection
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Comprehensive Obstetrics & Gynecology Medical
Coding Guide
Table of Contents
1. Foundations & E/M Coding in OB/GYN
2. Gynecology: Office & Inpatient Procedures
o Preventive Medicine
o Vulvar, Vaginal, Cervical Procedures
o Uterine & Endometrial Procedures
o Laparoscopic & Open Surgeries
o Pelvic Floor & Urogynecology
3. Obstetrics: The Global Package & Beyond
o Antepartum, Delivery, Postpartum
o High-Risk Obstetrics
o Ultrasound & Fetal Testing
4. ICD-10-CM Deep Dive
o 7th Character Specifics (Fetus, Trimester, Episode of Care)
o Complication Codes (O00–O9A)
o Z Codes for Supervision
5. Modifiers in Depth
6. Payer-Specific Rules (Medicare, Medicaid, Commercial)
7. Denial Prevention & Audit Checklists
8. Clinical Scenarios with Full Coding Pathways
Section 1: Foundations & E/M Coding
Evaluation & Management (E/M) Guidelines for 2024–2025
OB/GYN uses the Medical Decision Making (MDM) or Time methodology for office/outpatient
visits (99202–99215). Inpatient visits (99221–99233) use time or MDM as well.
Key OB/GYN E/M Codes
1|Page
, OBSTETRICS & GYNECOLOGY MEDICAL CODING GUIDE
Setting Code Range Typical Use
Office New Patient 99202–99205 First OB intake, new GYN consult
Office Established 99212–99215 Follow-up visits, postoperative checks
Inpatient Initial 99221–99223 Admission for preterm labor, postpartum complicat
Inpatient Subsequent 99231–99233 Daily rounding on hospitalized OB/GYN patient
Observation 99218–99220 Rule-out ectopic, hyperemesis, preterm labor moni
Consultations 99242–99245 (outpatient) Rarely used by commercial; Medicare no longer rec
Time vs. MDM in OB/GYN
• Time-based: Includes total time on date of encounter (prep, chart review, counseling,
care coordination). Document total time and what was done.
• MDM-based: Based on problems, data, risk. Example: A patient with abnormal
bleeding (moderate risk) + labs + prescription = Level 3 or 4.
Example Documentation:
"Total time spent with patient and family today was 45 minutes. I reviewed outside records,
performed a pelvic exam, counseled on endometriosis treatment options including hormonal
therapy and surgery, and coordinated referral to reproductive endocrinology." → 99205 (new
patient) or 99215 (established).
Section 2: Gynecology – Detailed Coding
2.1 Preventive Medicine (Annual Exams)
Patient Status Age Code
New patient Under 1 year 99381
New patient 1–4 99382
New patient 5–11 99383
New patient 12–17 99384
New patient 18–39 99385
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, OBSTETRICS & GYNECOLOGY MEDICAL CODING GUIDE
Patient Status Age Code
New patient 40–64 99386
New patient 65+ 99387
Established Under 1 year 99391
Established 1–4 99392
Established 5–11 99393
Established 12–17 99394
Established 18–39 99395
Established 40–64 99396
Established 65+ 99397
HCPCS for Medicare/Medicaid:
• G0101 – Cervical/vaginal cancer screening (Pap) – frequency per payer
• Q0091 – Screening Pap smear collection (often billed with G0101)
Modifier -25: Append when a problem is addressed during an annual exam (e.g., UTI, vaginitis,
breast lump). Bill preventive code + E/M code (e.g., 99395 + 99213-25).
2.2 Vulvar & Vaginal Procedures
Procedure CPT Details & Notes
Vulvar biopsy (single) 56605 Includes local anesthesia
Vulvar biopsy (each add'l) +56606 Use modifier -51 or -59 as required
Vulvar vestibulectomy 56620 Complete; for vestibulodynia
Vaginal biopsy 57100 Simple, single site
Vaginectomy (partial) 57106 Includes mucosa resection
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