2027 ICD-10-CM Diagnosis Code O99.345Other mental disorders complicating the puerperium

ICD-10-CM Codes›O00-O9A›O94-O9A›O99

ICD-10-CM O99.345
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

O99.345 is a billable ICD-10-CM diagnosis code for other mental disorders complicating the puerperium. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 769, 776. The code is restricted by the Medicare Code Editor to maternity cases (age 9 through 64). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Complications specified during the puerperium and Miscellaneous mental and behavioral disorders/conditions.

Code Identity

ICD-10-CM Code
O99.345
Billable Status
Yes — Valid for Submission
Code Describes
Other mental disorders complicating the puerperium
Short Description
Other mental disorders complicating the puerperium
Same as the full description in the CMS dataset.
Parent Code
O99.34
Other mental disorders complicating pregnancy, childbirth, and the puerperium

Code Classification

ChapterO00-O9APregnancy, childbirth and the puerperium
SectionO94-O9AOther obstetric conditions, not elsewhere classified
CategoryO99Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium
This CodeO99.345Other mental disorders complicating the puerperium

Code EditsBilling

Medicare Code Editor checks that affect claim validity for O99.345.

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.

  • Bipolar affective disorder, most recent episode mixed
  • Bipolar disorder, most recent episode manic
  • Bipolar I disorder, most recent episode depressed with postpartum onset
  • Bipolar I disorder, most recent episode depression
  • Bipolar I disorder, most recent episode manic
  • Bipolar I disorder, most recent episode manic with postpartum onset
  • Bipolar I disorder, most recent episode mixed with postpartum onset
  • Mental disorder during puerperium
  • Postpartum adjustment disorder
  • Postpartum anxiety
  • Postpartum depression
  • Recurrent major depressive disorder with postpartum onset

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to O99.345: its own notes plus those printed at O99.34, O99, and 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.

From O99 Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium applies to 96 codes
  • conditions which complicate the pregnant state, are aggravated by the pregnancy or are a main reason for obstetric care

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.

From O99.34 Other mental disorders complicating pregnancy, childbirth, and the puerperium applies to 6 codes
  • postpartum mood disturbance (O90.6)
  • postnatal psychosis (F53.1)
  • puerperal psychosis (F53.1)
From O99 Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium applies to 96 codes
  • when the reason for maternal care is that the condition is known or suspected to have affected the fetus (O35-O36)
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 O99 Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium applies to 96 codes
  • code to identify specific 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.

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

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

CCSR PRG027
Complications specified during the puerperium
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR MBD013
Miscellaneous mental and behavioral disorders/conditions
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Mental Disorders

Mental disorders (or mental illnesses) are conditions that affect your thinking, feeling, mood, and behavior. They may happen over a short period of time or come and go. Some can be chronic (long-lasting). They can affect your ability to relate to others and function each day..

The full article covers:

  • What are mental disorders?
  • What are some types of mental disorders?
  • What causes mental disorders?
  • Who is at risk for mental disorders?
  • How are mental disorders diagnosed?
  • What are the treatments for mental disorders?

Read the full article at MedlinePlus

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

Convert O99.345 to ICD-9-CMHistory

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

ICD-9-CM
648.42 Mental dis-deliv w p/p
Approximate The match is approximate rather than exact.
ICD-9-CM
648.44 Mental disorder-postpart
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About O99.345Overview

What is the ICD-10 code for other mental disorders complicating the puerperium?

The ICD-10-CM code for other mental disorders complicating the puerperium is O99.345 (sometimes written as O99345). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is O99.345 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other mental disorders complicating the puerperium on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does O99.345 group to?

When other mental disorders complicating the puerperium is the principal diagnosis on an inpatient stay, it groups to MS-DRG 769, 776, with relative weights from 0.6718 to 1.6666 depending on complications. Higher weights mean higher Medicare reimbursement.

Who can O99.345 be reported for?

The Medicare Code Editor checks other mental disorders complicating the puerperium against patient demographics: this code is intended for maternity cases (age 9 through 64). Claims outside these limits are flagged as inconsistent.

Does O99.345 need an additional code?

When the condition applies, yes. The Use Additional Code note at O99, which applies to O99.345, reads: code to identify specific condition. The additional code is reported after O99.345.