Pre-existing hypertension complicating pregnancy, childbirth and the puerperium (O10) ICD-10-CM
The O10 code range covers pre-existing hypertension complicating pregnancy, childbirth and the puerperium with 49 ICD-10-CM diagnosis codes. 36 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Includes
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
- pre-existing hypertension with pre-existing proteinuria complicating pregnancy, childbirth and the puerperium
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
- pre-existing hypertension with superimposed pre-eclampsia complicating pregnancy, childbirth and the puerperium O11
Codes in the O10 Range 49 codes · 36 billable
- O10 Pre-existing hypertension complicating pregnancy, childbirth and the puerperiumNon-billable
- O10.0 Pre-existing essential hypertension complicating pregnancy, childbirth and the puerperiumNon-billable
- O10.01 Pre-existing essential hypertension complicating pregnancyNon-billable
- O10.011 Pre-existing essential hypertension complicating pregnancy, first trimester
- O10.012 Pre-existing essential hypertension complicating pregnancy, second trimester
- O10.013 Pre-existing essential hypertension complicating pregnancy, third trimester
- O10.019 Pre-existing essential hypertension complicating pregnancy, unspecified trimester
- O10.02 Pre-existing essential hypertension complicating childbirth
- O10.03 Pre-existing essential hypertension complicating the puerperium
- O10.1 Pre-existing hypertensive heart disease complicating pregnancy, childbirth and the puerperiumNon-billable
- O10.11 Pre-existing hypertensive heart disease complicating pregnancyNon-billable
- O10.111 Pre-existing hypertensive heart disease complicating pregnancy, first trimester
- O10.112 Pre-existing hypertensive heart disease complicating pregnancy, second trimester
- O10.113 Pre-existing hypertensive heart disease complicating pregnancy, third trimester
- O10.119 Pre-existing hypertensive heart disease complicating pregnancy, unspecified trimester
- O10.12 Pre-existing hypertensive heart disease complicating childbirth
- O10.13 Pre-existing hypertensive heart disease complicating the puerperium
- O10.2 Pre-existing hypertensive chronic kidney disease complicating pregnancy, childbirth and the puerperiumNon-billable
- O10.21 Pre-existing hypertensive chronic kidney disease complicating pregnancyNon-billable
- O10.211 Pre-existing hypertensive chronic kidney disease complicating pregnancy, first trimester
- O10.212 Pre-existing hypertensive chronic kidney disease complicating pregnancy, second trimester
- O10.213 Pre-existing hypertensive chronic kidney disease complicating pregnancy, third trimester
- O10.219 Pre-existing hypertensive chronic kidney disease complicating pregnancy, unspecified trimester
- O10.22 Pre-existing hypertensive chronic kidney disease complicating childbirth
- O10.23 Pre-existing hypertensive chronic kidney disease complicating the puerperium
- O10.3 Pre-existing hypertensive heart and chronic kidney disease complicating pregnancy, childbirth and the puerperiumNon-billable
- O10.31 Pre-existing hypertensive heart and chronic kidney disease complicating pregnancyNon-billable
- O10.311 Pre-existing hypertensive heart and chronic kidney disease complicating pregnancy, first trimester
- O10.312 Pre-existing hypertensive heart and chronic kidney disease complicating pregnancy, second trimester
- O10.313 Pre-existing hypertensive heart and chronic kidney disease complicating pregnancy, third trimester
- O10.319 Pre-existing hypertensive heart and chronic kidney disease complicating pregnancy, unspecified trimester
- O10.32 Pre-existing hypertensive heart and chronic kidney disease complicating childbirth
- O10.33 Pre-existing hypertensive heart and chronic kidney disease complicating the puerperium
- O10.4 Pre-existing secondary hypertension complicating pregnancy, childbirth and the puerperiumNon-billable
- O10.41 Pre-existing secondary hypertension complicating pregnancyNon-billable
- O10.411 Pre-existing secondary hypertension complicating pregnancy, first trimester
- O10.412 Pre-existing secondary hypertension complicating pregnancy, second trimester
- O10.413 Pre-existing secondary hypertension complicating pregnancy, third trimester
- O10.419 Pre-existing secondary hypertension complicating pregnancy, unspecified trimester
- O10.42 Pre-existing secondary hypertension complicating childbirth
- O10.43 Pre-existing secondary hypertension complicating the puerperium
- O10.9 Unspecified pre-existing hypertension complicating pregnancy, childbirth and the puerperiumNon-billable
- O10.91 Unspecified pre-existing hypertension complicating pregnancyNon-billable
- O10.911 Unspecified pre-existing hypertension complicating pregnancy, first trimester
- O10.912 Unspecified pre-existing hypertension complicating pregnancy, second trimester
- O10.913 Unspecified pre-existing hypertension complicating pregnancy, third trimester
- O10.919 Unspecified pre-existing hypertension complicating pregnancy, unspecified trimester
- O10.92 Unspecified pre-existing hypertension complicating childbirth
- O10.93 Unspecified pre-existing hypertension complicating the puerperium
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the O10 range.
Eclampsia
Onset of HYPERREFLEXIA; SEIZURES; or COMA in a previously diagnosed pre-eclamptic patient (PRE-ECLAMPSIA).
Hypertensive Crisis
A severe, acute increase in BLOOD PRESSURE that may result in STROKE or MYOCARDIAL ISCHEMIA.
Pre-Eclampsia
A complication of PREGNANCY, characterized by a complex of symptoms including maternal HYPERTENSION and PROTEINURIA with or without pathological EDEMA. Symptoms may range between mild and severe. Pre-eclampsia usually occurs after the 20th week of gestation, but may develop before this time in the presence of trophoblastic disease.
About the O10 Code Range
The ICD-10 code section O10 encompasses diagnoses for pre-existing hypertension that complicates pregnancy, childbirth, and the puerperium. These codes help document various forms of hypertension, including essential, secondary, hypertensive heart disease, and chronic kidney disease-associated hypertension, as they affect maternal health during different pregnancy stages and delivery.
Codes like O10.0 specify essential hypertension, while O10.1, O10.2, and O10.3 further categorize cases involving hypertensive heart disease, chronic kidney disease, or both. The section addresses complications occurring in the first, second, or third trimesters as well as unspecified periods of pregnancy, childbirth, or the postpartum period (puerperium). For example, O10.011 denotes essential hypertension in the first trimester, and O10.019 covers unspecified trimester cases. Synonyms associated with these conditions include "benign essential hypertension," "malignant hypertension," and "hypertensive crisis," helping coders select the precise ICD-10 code for hypertension complicating pregnancy. Understanding this classification aids in accurate reporting of maternal hypertension’s impact on pregnancy outcomes and care management.
Questions About This Page
How many billable codes are in the O10 range?
Of the 49 codes in this range, 36 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the O10 range classify?
The range classifies pre-existing hypertension complicating pregnancy, childbirth and the puerperium. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
