O91.111 Abscess of breast associated with pregnancy, first trimester

Billable ICD-10-CM code, FY2026.

Applies from O91 Infections of breast associated with pregnancy, the puerperium and lactation

Use additional code

• code to identify infection

Applies from O91.11 Abscess of breast associated with pregnancy

Applicable to

• Gestational mammary abscess
• Gestational purulent mastitis
• Gestational subareolar abscess

MS-DRG index

Defines the logic of DRG(s) 817-819 in MDC 14.

Approximate ICD-9-CM (GEMs)

• 675.11 Abscess of breast associated with childbirth, delivered, with or without mention of antepartum condition (approximate)
• 675.13 Abscess of breast associated with childbirth, antepartum condition or complication (approximate)

Medicare Code Edits (MCE v43.1 (April 2026))

• Maternity diagnoses (age 9 through 64): Age conflict edit. These diagnoses are clinically expected only in patients age 9 through 64.

Code annotations containing back-references to O91.111

Back-references to O91

• Type 1 Excludes: N61 Inflammatory disorders of breast ("inflammatory disorder of breast associated with childbirth (O91.-)")

Nearby codes

• O91.019 Infection of nipple associated with pregnancy, unspecified trimester
• O91.02 Infection of nipple associated with the puerperium
• O91.03 Infection of nipple associated with lactation
• O91.1 Abscess of breast associated with pregnancy, the puerperium and lactation
• O91.11 Abscess of breast associated with pregnancy
• O91.111 Abscess of breast associated with pregnancy, first trimester (this code)
• O91.112 Abscess of breast associated with pregnancy, second trimester
• O91.113 Abscess of breast associated with pregnancy, third trimester
• O91.119 Abscess of breast associated with pregnancy, unspecified trimester
• O91.12 Abscess of breast associated with the puerperium
• O91.13 Abscess of breast associated with lactation