2027 ICD-10-CM Diagnosis Code O10Pre-existing hypertension complicating pregnancy, childbirth and the puerperium

ICD-10-CM Codes›O00-O9A›O10-O16›O10

ICD-10-CM O10
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

O10 is a non-billable ICD-10-CM category code for pre-existing hypertension complicating pregnancy, childbirth and the puerperium, so it cannot be submitted on claims. Use a more specific code from this category instead, such as O10.011, O10.012, O10.013, and O10.019.

Code Identity

ICD-10-CM Code
O10
Billable Status
No — Non-Billable Category
Code Describes
Pre-existing hypertension complicating pregnancy, childbirth and the puerperium
Short Description
Pre-existing hypertension compl preg/chldbrth
Chapter
O10-O16
Edema, proteinuria and hypertensive disorders in pregnancy, childbirth and the puerperium

Code Classification

ChapterO00-O9APregnancy, childbirth and the puerperium
SectionO10-O16Edema, proteinuria and hypertensive disorders in pregnancy, childbirth and the puerperium
CategoryO10Pre-existing hypertension complicating pregnancy, childbirth and the puerperium
This CodeO10Pre-existing hypertension complicating pregnancy, childbirth and the puerperium

Specific Coding for Pre-existing hypertension compl preg/chldbrthOverview

Non-specific codes like O10 require more characters. Use one of these billable codes instead:

  • O10.0 for Pre-existing essential hypertension complicating pregnancy, childbirth and the puerperium

  • O10.01 for Pre-existing essential hypertension complicating pregnancy

  • Use O10.02 for Pre-existing essential hypertension complicating childbirth

  • Use O10.03 for Pre-existing essential hypertension complicating the puerperium

  • O10.1 for Pre-existing hypertensive heart disease complicating pregnancy, childbirth and the puerperium

  • O10.11 for Pre-existing hypertensive heart disease complicating pregnancy

  • Use O10.12 for Pre-existing hypertensive heart disease complicating childbirth

  • Use O10.13 for Pre-existing hypertensive heart disease complicating the puerperium

  • O10.2 for Pre-existing hypertensive chronic kidney disease complicating pregnancy, childbirth and the puerperium

  • O10.21 for Pre-existing hypertensive chronic kidney disease complicating pregnancy

  • Use O10.22 for Pre-existing hypertensive chronic kidney disease complicating childbirth

  • Use O10.23 for Pre-existing hypertensive chronic kidney disease complicating the puerperium

  • O10.3 for Pre-existing hypertensive heart and chronic kidney disease complicating pregnancy, childbirth and the puerperium

  • O10.31 for Pre-existing hypertensive heart and chronic kidney disease complicating pregnancy

  • Use O10.32 for Pre-existing hypertensive heart and chronic kidney disease complicating childbirth

  • Use O10.33 for Pre-existing hypertensive heart and chronic kidney disease complicating the puerperium

  • O10.4 for Pre-existing secondary hypertension complicating pregnancy, childbirth and the puerperium

  • O10.41 for Pre-existing secondary hypertension complicating pregnancy

  • Use O10.42 for Pre-existing secondary hypertension complicating childbirth

  • Use O10.43 for Pre-existing secondary hypertension complicating the puerperium

  • O10.9 for Unspecified pre-existing hypertension complicating pregnancy, childbirth and the puerperium

  • O10.91 for Unspecified pre-existing hypertension complicating pregnancy

  • Use O10.92 for Unspecified pre-existing hypertension complicating childbirth

  • Use O10.93 for Unspecified pre-existing hypertension complicating the puerperium

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to O10: its own notes plus those printed at Chapter 15. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

  • pre-existing hypertension with pre-existing proteinuria complicating pregnancy, childbirth and the puerperium

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Chapter 15 (O00-O9A) Pregnancy, childbirth and the puerperium applies to 2,481 codes
  • supervision of normal pregnancy (Z34.-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

On O10 itself
  • pre-existing hypertension with superimposed pre-eclampsia complicating pregnancy, childbirth and the puerperium (O11.-)
From Chapter 15 (O00-O9A) Pregnancy, childbirth and the puerperium applies to 2,481 codes
  • mental and behavioral disorders associated with the puerperium (F53.-)
  • obstetrical tetanus (A34)
  • postpartum necrosis of pituitary gland (E23.0)
  • puerperal osteomalacia (M83.0)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 15 (O00-O9A) Pregnancy, childbirth and the puerperium applies to 2,481 codes
  • code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.

Notes

General instructions on how these codes are used.

From Chapter 15 (O00-O9A) Pregnancy, childbirth and the puerperium applies to 2,481 codes
  • CODES FROM THIS CHAPTER ARE FOR USE ONLY ON MATERNAL RECORDS, NEVER ON NEWBORN RECORDS
  • Codes from this chapter are for use for conditions related to or aggravated by the pregnancy, childbirth, or by the puerperium (maternal causes or obstetric causes)
  • Trimesters are counted from the first day of the last menstrual period. They are defined as follows:
  • 1st trimester- less than 14 weeks 0 days
  • 2nd trimester- 14 weeks 0 days to less than 28 weeks 0 days
  • 3rd trimester- 28 weeks 0 days until delivery

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name O10, its category, or a range that includes it.

Includes 2

These notes mention O10.

  • O11 Pre-existing hypertension with pre-eclampsia
    conditions in O10 complicated by pre-eclampsia
  • O15 Eclampsia
    convulsions following conditions in O10-O14 and O16

Applicable To 1

These notes mention O10.

  • P00.0 Newborn affected by maternal hypertensive disorders
    Newborn affected by maternal conditions classifiable to O10-O11, O13-O16

Excludes1 1

These codes carry an Excludes1 note naming O10: they are not reported together with it, unless the two conditions are unrelated.

  • I10 Essential (primary) hypertension
    hypertensive disease complicating pregnancy, childbirth and the puerperium (O10-O11, O13-O16)

Excludes2 2

These codes carry an Excludes2 note naming O10: its condition is not part of those codes, and both may be reported when the patient has both.

  • Block I10-I1A Hypertensive diseases
    hypertensive disease complicating pregnancy, childbirth and the puerperium (O10-O11, O13-O16)
  • O99.4 Diseases of the circulatory system complicating pregnancy, childbirth and the puerperium
    hypertensive disorders (O10-O16)

Use Additional Code 1

These codes say to use an additional code from the note, and O10 is one of the codes named.

  • O11 Pre-existing hypertension with pre-eclampsia
    code from O10 to identify the type of hypertension

Patient EducationClinical

Health Problems in Pregnancy

A health problem in pregnancy is any disease or condition that could affect your health or the health of your fetus. Some health problems may make it more likely that you will have a high-risk pregnancy. A high-risk pregnancy is one in which you, your fetus, or both are at higher risk for health problems than in a typical pregnancy.

The full article covers:

  • What are health problems in pregnancy?
  • What raises my risk for health problems during pregnancy?
  • Can chronic health conditions cause problems in pregnancy?
  • Can health problems in pregnancy be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About O10Overview

Is O10 a billable code?

No. This is a category header that groups the codes for pre-existing hypertension complicating pregnancy, childbirth and the puerperium, and headers cannot be submitted on claims. Claims for pre-existing hypertension complicating pregnancy, childbirth and the puerperium need a more specific code from this category, such as O10.011, O10.012, and O10.013.