2024 ICD-10-CM Diagnosis Code O91.211

Nonpurulent mastitis associated with pregnancy, first trimester

ICD-10-CM Code:
O91.211
ICD-10 Code for:
Nonpurulent mastitis associated w pregnancy, first trimester
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Not chronic
Code Navigator:

Code Classification

  • Pregnancy, childbirth and the puerperium
    (O00-O9A)
    • Complications predominantly related to the puerperium
      (O85-O92)
      • Infections of breast associated with pregnancy, the puerperium and lactation
        (O91)

O91.211 is a billable diagnosis code used to specify a medical diagnosis of nonpurulent mastitis associated with pregnancy, first trimester. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

The code O91.211 is applicable to female patients aged 12 through 55 years inclusive. It is clinically and virtually impossible to use this code on a non-female patient outside the stated age range.

Clinical Classification

Clinical CategoryCCSR Category CodeInpatient Default CCSROutpatient Default CCSR
Nonmalignant breast conditionsGEN017N - Not default inpatient assignment for principal diagnosis or first-listed diagnosis.N - Not default outpatient assignment for principal diagnosis or first-listed diagnosis.
Other specified complications in pregnancyPRG028Y - Yes, default inpatient assignment for principal diagnosis or first-listed diagnosis.Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10-CM Code Edits are applicable to this code:

  • 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).
  • Diagnoses for females only - The Medicare Code Editor detects inconsistencies between a patient’s sex and any diagnosis on the patient’s record, these edits apply to FEMALES only .

Convert O91.211 to ICD-9-CM

  • ICD-9-CM Code: 675.21 - Mastitis-delivered
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.
  • ICD-9-CM Code: 675.23 - Mastitis-antepartum
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

Patient Education


Breast Diseases

Most women experience breast changes at some time. Your age, hormone levels, and medicines you take may cause lumps, bumps, and discharges (fluids that are not breast milk).

If you have a breast lump, pain, discharge or skin irritation, see your health care provider. Minor and serious breast problems have similar symptoms. Although many women fear cancer, most breast problems are not cancer.

Some common breast changes are:

  • Fibrocystic breast changes - lumpiness, thickening and swelling, often just before a woman's period
  • Cysts - fluid-filled lumps
  • Fibroadenomas - solid, round, rubbery lumps that move easily when pushed, occurring most in younger women
  • Intraductal papillomas - growths similar to warts near the nipple
  • Blocked milk ducts
  • Milk production when a woman is not breastfeeding

NIH: National Cancer Institute


[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.

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.