2021 ICD-10-CM Code O91.21

Nonpurulent mastitis associated with pregnancy

Version 2021
Non-Billable Code

Not Valid for Submission

O91.21 is a "header" nonspecific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of nonpurulent mastitis associated with pregnancy. The code is NOT valid for the year 2021 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

ICD-10:O91.21
Short Description:Nonpurulent mastitis associated with pregnancy
Long Description:Nonpurulent mastitis associated with pregnancy

Code Classification

Specific Coding for Nonpurulent mastitis associated with pregnancy

Header codes like O91.21 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10 codes with a higher level of specificity when coding for nonpurulent mastitis associated with pregnancy:

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code O91.21:


Inclusion Terms

Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code O91.21 are found in the index:

Information for Patients


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

NIH: National Cancer Institute


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Health Problems in Pregnancy

Every pregnancy has some risk of problems. You may have problems because of a health condition you had before you got pregnant. You could also develop a condition during pregnancy. Other causes of problems during pregnancy can include being pregnant with more than one baby, a health problem in a previous pregnancy, substance abuse during pregnancy, or being over age 35. Any of these can affect your health, the health of your baby, or both.

If you have a chronic condition, you should talk to your health care provider about how to minimize your risk before you get pregnant. Once you are pregnant, you may need a health care team to monitor your pregnancy. Some common conditions that can complicate a pregnancy include

Other conditions that can make pregnancy risky can happen while you are pregnant - for example, gestational diabetes and Rh incompatibility. Good prenatal care can help detect and treat them.

Some discomforts, like nausea, back pain, and fatigue, are common during pregnancy. Sometimes it is hard to know what is normal. Call your health care provider if something is bothering or worrying you.


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Code History

  • 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 (First year ICD-10-CM implemented into the HIPAA code set)