O91 — Infections of breast associated with pregnancy, the puerperium and lactation
Is O91 billable?
No — O91 is a non-billable header code. O91 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 18 billable codes beneath O91.
Billable codes under this header
- O91.02Infection of nipple associated with the puerperium
- O91.03Infection of nipple associated with lactation
- O91.12Abscess of breast associated with the puerperium
- O91.13Abscess of breast associated with lactation
- O91.22Nonpurulent mastitis associated with the puerperium
- O91.23Nonpurulent mastitis associated with lactation
- O91.011Infection of nipple associated with pregnancy, first trimester
- O91.012Infection of nipple associated with pregnancy, second trimester
- O91.013Infection of nipple associated with pregnancy, third trimester
- O91.019Infection of nipple associated with pregnancy, unspecified trimester
- O91.111Abscess of breast associated with pregnancy, first trimester
- O91.112Abscess of breast associated with pregnancy, second trimester
- O91.113Abscess of breast associated with pregnancy, third trimester
- O91.119Abscess of breast associated with pregnancy, unspecified trimester
- O91.211Nonpurulent mastitis associated with pregnancy, first trimester
- O91.212Nonpurulent mastitis associated with pregnancy, second trimester
- O91.213Nonpurulent mastitis associated with pregnancy, third trimester
- O91.219Nonpurulent mastitis associated with pregnancy, unspecified trimester
O91 at a glance
| Code | O91 |
|---|---|
| Description | Infections of breast associated with pregnancy, the puerperium and lactation |
| Billable | No — header code |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Use additional code
Report an additional code alongside O91 to fully describe the condition. O91 is sequenced first.
- code to identify infection
Excludes1 — never code together — inherited from Chapter 15
The conditions below can never be reported together with O91 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- supervision of normal pregnancy (Z34.-)
Use additional code — inherited from Chapter 15
Report an additional code alongside O91 to fully describe the condition. O91 is sequenced first.
- code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.
Excludes2 — not included here — inherited from Chapter 15
The conditions below are not part of O91, but a patient may have both at the same time. When documentation supports it, O91 and the excluded code may both be reported.
Excludes2 — not included here — inherited from O85-O92
The conditions below are not part of O91, but a patient may have both at the same time. When documentation supports it, O91 and the excluded code may both be reported.
What codes fall under O91? (3)
How long has O91 existed?
O91 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.