ICD-10-CM 2027
ICD-10 code for breast agenesis
From the official ICD-10-CM alphabetic index entry “Agenesis › breast (with nipple present)”. Page updated September 29, 2026.
About coding breast agenesis
The ICD-10-CM code for breast agenesis is Q83.8 (Other congenital malformations of breast). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on Q83.8.
Within Q83, choose Q83.8 (Other congenital malformations of breast) only when documentation doesn't support a more specific option: congenital absence of breast with absent nipple (Q83.0), accessory breast (Q83.1), absent nipple (Q83.2), accessory nipple (Q83.3) and congenital malformation of breast, unspecified (Q83.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 600 (Non-Malignant Breast Disorders with CC/MCC, relative weight 0.9975) and DRG 601 (Non-Malignant Breast Disorders without CC/MCC, relative weight 0.6017), in MDC 09 (Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific breast agenesis codes (official index)
- with absent nipple Q83.0 — Congenital absence of breast with absent nipple
Common questions about breast agenesis ICD-10 codes
What is the ICD-10 code for breast agenesis?
- Q83.8 — Other congenital malformations of breast. More specific codes apply when the documentation supports them: Q83.0.
Is Q83.8 billable?
- Yes. Q83.8 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can Q83.8 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict Q83.8 as a principal diagnosis.
Is Q83.8 a CC or MCC?
- No. Q83.8 is neither a CC nor an MCC under MS-DRG v44.0.