O91

Infections of breast associated with pregnancy, the puerperium and lactation

Diagnosis reference

Nonbillable category

This entry is a category or subcategory. Choose the appropriate billable descendant based on the clinical documentation.

Effective periodOctober 1, 2026–September 30, 2027

SourceCMS ICD-10-CM order file

ClassificationDiagnosis · clinical modification

Related entries

Up to 30 descendants in this category

CODE	DESCRIPTION	TYPE
O91.0	Infection of nipple associated with pregnancy, the puerperium and lactation	Category
O91.01	Infection of nipple associated with pregnancy	Category
O91.011	Infection of nipple associated with pregnancy, first trimester	Billable
O91.012	Infection of nipple associated with pregnancy, second trimester	Billable
O91.013	Infection of nipple associated with pregnancy, third trimester	Billable
O91.019	Infection of nipple associated with pregnancy, unspecified trimester	Billable
O91.02	Infection of nipple associated with the puerperium	Billable
O91.03	Infection of nipple associated with lactation	Billable
O91.1	Abscess of breast associated with pregnancy, the puerperium and lactation	Category
O91.11	Abscess of breast associated with pregnancy	Category
O91.111	Abscess of breast associated with pregnancy, first trimester	Billable
O91.112	Abscess of breast associated with pregnancy, second trimester	Billable
O91.113	Abscess of breast associated with pregnancy, third trimester	Billable
O91.119	Abscess of breast associated with pregnancy, unspecified trimester	Billable
O91.12	Abscess of breast associated with the puerperium	Billable
O91.13	Abscess of breast associated with lactation	Billable
O91.2	Nonpurulent mastitis associated with pregnancy, the puerperium and lactation	Category
O91.21	Nonpurulent mastitis associated with pregnancy	Category
O91.211	Nonpurulent mastitis associated with pregnancy, first trimester	Billable
O91.212	Nonpurulent mastitis associated with pregnancy, second trimester	Billable
O91.213	Nonpurulent mastitis associated with pregnancy, third trimester	Billable
O91.219	Nonpurulent mastitis associated with pregnancy, unspecified trimester	Billable
O91.22	Nonpurulent mastitis associated with the puerperium	Billable
O91.23	Nonpurulent mastitis associated with lactation	Billable

Use the complete reference

This reference does not reproduce the full tabular hierarchy, inclusion notes, Excludes1/2 notes, sequencing instructions, or seventh-character rules. Review the official tables and coding guidelines.

Open official CMS files

ICD-10-CM codes describe diagnoses. They do not have an independent Medicare PFS reimbursement amount, and billability alone does not establish coverage.