O11.9 — Pre-existing hypertension with pre-eclampsia, unspecified trimester
Is O11.9 billable?
Yes, but O11.9 is an unspecified code. O11.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, O11.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting O11.9 — the more specific alternatives are listed below.
More specific alternatives
- O11.1Pre-existing hypertension with pre-eclampsia, first trimester
- O11.2Pre-existing hypertension with pre-eclampsia, second trimester
- O11.3Pre-existing hypertension with pre-eclampsia, third trimester
- O11.4Pre-existing hypertension with pre-eclampsia, complicating childbirth
- O11.5Pre-existing hypertension with pre-eclampsia, complicating the puerperium
O11.9 at a glance
| Code | O11.9 |
|---|---|
| Description | Pre-existing hypertension with pre-eclampsia, unspecified trimester |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does O11.9 group to?
O11.9 sits in MDC 14 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 817Other Antepartum Diagnoses with O.R. Procedures with MCCsurgical
- 818Other Antepartum Diagnoses with O.R. Procedures with CCsurgical
- 819Other Antepartum Diagnoses with O.R. Procedures without CC/MCCsurgical
Excludes1 — never code together — inherited from Chapter 15
The conditions below can never be reported together with O11.9 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- supervision of normal pregnancy (Z34.-)
Use additional code — inherited from Chapter 15
Report an additional code alongside O11.9 to fully describe the condition. O11.9 is sequenced first.
- code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.
Use additional code — inherited from O11
Report an additional code alongside O11.9 to fully describe the condition. O11.9 is sequenced first.
- code from O10 to identify the type of hypertension
Excludes2 — not included here — inherited from Chapter 15
The conditions below are not part of O11.9, but a patient may have both at the same time. When documentation supports it, O11.9 and the excluded code may both be reported.
How long has O11.9 existed?
O11.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
What other codes are in the O11 family? (5)
- O11.1Pre-existing hypertension with pre-eclampsia, first trimester
- O11.2Pre-existing hypertension with pre-eclampsia, second trimester
- O11.3Pre-existing hypertension with pre-eclampsia, third trimester
- O11.4Pre-existing hypertension with pre-eclampsia, complicating childbirth
- O11.5Pre-existing hypertension with pre-eclampsia, complicating the puerperium