2026 ICD-10-CM Diagnosis Code O14.00Mild to moderate pre-eclampsia, unspecified trimester

ICD-10-CM Codes›O00-O9A›O10-O16›O14

ICD-10-CM O14.00
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

O14.00 is a billable ICD-10-CM diagnosis code for mild to moderate pre-eclampsia, unspecified trimester. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 817 through 819, 831 through 833. The code is restricted by the Medicare Code Editor to maternity cases (age 9 through 64). Coders also document this condition as mild pre-eclampsia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Hypertension and hypertensive-related conditions complicating pregnancy; childbirth; and the puerperium.

Code Identity

ICD-10-CM Code
O14.00
Billable Status
Yes — Valid for Submission
Code Describes
Mild to moderate pre-eclampsia, unspecified trimester
Short Description
Mild to moderate pre-eclampsia, unspecified trimester
Same as the full description in the CMS dataset.
Parent Code
O14.0
Mild to moderate pre-eclampsia

Code Classification

ChapterO00-O9APregnancy, childbirth and the puerperium
SectionO10-O16Edema, proteinuria and hypertensive disorders in pregnancy, childbirth and the puerperium
CategoryO14Pre-eclampsia
This CodeO14.00Mild to moderate pre-eclampsia, unspecified trimester

Code EditsBilling

Medicare Code Editor checks that affect claim validity for O14.00.

Maternity diagnoses
The Medicare Code Editor detects inconsistencies in maternity cases by checking a patient's age and any diagnosis on the patient's record. The maternity code edits apply to patients age ange is 9–64 years inclusive (e.g., diabetes in pregnancy, antepartum pulmonary complication).

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Mild pre-eclampsia
  • Moderate proteinuric hypertension of pregnancy
  • Pre-eclampsia

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR PRG020
Hypertension and hypertensive-related conditions complicating pregnancy; childbirth; and the puerperium
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

High Blood Pressure in Pregnancy

Blood pressure is the force of your blood pushing against the walls of your arteries. Your arteries are blood vessels that carry blood from your heart to other parts of your body. High blood pressure, or hypertension, is blood pressure that is higher than normal.

The full article covers:

  • What is high blood pressure in pregnancy?
  • What are the types of high blood pressure in pregnancy?
  • Who is more likely to develop high blood pressure in pregnancy?
  • What are the symptoms of high blood pressure in pregnancy?
  • What problems can high blood pressure in pregnancy cause?
  • How is high blood pressure in pregnancy diagnosed?
  • What are the treatments for high blood pressure in pregnancy?

Read the full article at MedlinePlus

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

Convert O14.00 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
642.40 Mild/NOS preeclamp-unsp
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About O14.00Overview

Is O14.00 (Mild to moderate pre-eclampsia) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report mild to moderate pre-eclampsia, unspecified trimester on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does O14.00 group to?

When mild to moderate pre-eclampsia, unspecified trimester is the principal diagnosis on an inpatient stay, it groups to MS-DRG 817, 818, 819, 831, 832, 833, with relative weights from 0.5229 to 1.6880 depending on complications. Higher weights mean higher Medicare reimbursement.

Who can O14.00 be reported for?

The Medicare Code Editor checks mild to moderate pre-eclampsia, unspecified trimester against patient demographics: this code is intended for maternity cases (age 9 through 64). Claims outside these limits are flagged as inconsistent.

What is the ICD-9 equivalent of O14.00?

Under the General Equivalence Mappings, mild to moderate pre-eclampsia, unspecified trimester converts to ICD-9-CM 642.40 (Mild/NOS preeclamp-unsp). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.