FY2027 ICD-10-CM reference
P56.99: Hydrops fetalis due to other hemolytic disease
By the HCC Buddy Coding Team
The official ICD-10-CM descriptor is Hydrops fetalis due to other hemolytic disease. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Billable code. Verified against the official FY2027 order file.
FY2027 Tabular instructions
Instructions below include applicable chapter, section and parent-code notes. Each note identifies where it appears in the official source.
Instructional note
Codes from this chapter are for use on newborn records only, never on maternal records
Source: P00-P96 (chapter, inherited).
Includes
conditions that have their origin in the fetal or perinatal period (before birth through the first 28 days after birth) even if morbidity occurs later
Source: P00-P96 (chapter, inherited).
Excludes2
congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
Source: P00-P96 (chapter, inherited).
Excludes2
endocrine, nutritional and metabolic diseases (E00-E88)
Source: P00-P96 (chapter, inherited).
Excludes2
injury, poisoning and certain other consequences of external causes (S00-T88)
Source: P00-P96 (chapter, inherited).
Excludes2
neoplasms (C00-D49)
Source: P00-P96 (chapter, inherited).
Excludes2
tetanus neonatorum (A33)
Source: P00-P96 (chapter, inherited).
Excludes1
congenital stenosis and stricture of bile ducts (Q44.3)
Source: P50-P61 (section, inherited).
Excludes1
Crigler-Najjar syndrome (E80.5)
Source: P50-P61 (section, inherited).
Excludes1
Dubin-Johnson syndrome (E80.6)
Source: P50-P61 (section, inherited).
Excludes1
Gilbert syndrome (E80.4)
Source: P50-P61 (section, inherited).
Excludes1
hereditary hemolytic anemias (D55-D58)
Source: P50-P61 (section, inherited).
Excludes1
hydrops fetalis NOS (P83.2)
Source: P56 (category, inherited).
Compare the FY2027 additions, removals and billable-status changes
What does P56.99 mean in FY2027?
The official ICD-10-CM descriptor is Hydrops fetalis due to other hemolytic disease. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Is P56.99 billable in FY2027?
The FY2027 order file marks P56.99 as billable. Check the complete Tabular instructions and documentation before assigning it.
Does P56.99 map to an HCC?
In the CMS 2027 Initial ICD-10-CM Mappings (payment year 2027, 2026 dates of service), P56.99 maps to CMS-HCC V28 HCC 109 (Acquired Hemolytic, Aplastic, and Sideroblastic Anemias). For 2027 dates of service, CMS has not yet published the payment year 2028 mappings. Under the PY2026 CMS mapping; CMS 2027 initial file unchanged: no ESRD category; no RxHCC category. Coefficients for these models are pending verification for payment year 2027. HHS-HCC: HCC 69 under the HHS-HCC 2026 benefit year mapping (no RAF; HHS-HCC weights vary by metal level). CMS-HCC V24: not used for payment year 2027 Medicare Advantage payment (CMS CY 2027 Rate Announcement). The PACE mapping is still pending verification for FY2027.
Source: CMS FY2027 ICD-10-CM order file. Payment model: CMS CY 2027 Rate Announcement. Read the FY2027 Official Guidelines.
Review the FY2026 April edition