O28 vs O99
O28 (Abnormal findings on antenatal screening of mother) compared with O99 (Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium), from the official CMS tabular data. Both may be reported when both conditions are documented (Excludes2).
Can these codes be reported together?
Yes, when both are documented. O28 carries an Excludes2 note covering O99: “maternal diseases classifiable elsewhere but complicating pregnancy, labor and delivery, and the puerperium (O98-O99)”
Excludes2 marks distinct conditions — both may be reported when both are documented.
Side by side
| O28Abnormal findings on antenatal screening of mother | O99Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | O00-O9A — Pregnancy, Childbirth and the Puerperium (O00-O9A) | O00-O9A — Pregnancy, Childbirth and the Puerperium (O00-O9A) |
| Definition | Abnormal findings on antenatal screening of mother is a non-billable ICD-10-CM category code (O28). | Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium is a non-billable ICD-10-CM category code (O99). |
| Includes | — | conditions which complicate the pregnant state, are aggravated by the pregnancy or are a main reason for obstetric care |
| Use additional code | — | code to identify specific condition |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources