P56.0 Hydrops fetalis due to isoimmunization

Billable ICD-10-CM code, FY2026. Acts as a Major Complication or Comorbidity (MCC) as a secondary diagnosis.

Applies from P56 Hydrops fetalis due to hemolytic disease

Excludes1 (never code together)

• hydrops fetalis NOS (P83.2)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 109 — Acquired Hemolytic, Aplastic, and Sideroblastic Anemias

MS-DRG index

Defines the logic of DRG(s) 791 in MDC 15.

Approximate ICD-9-CM (GEMs)

• 773.3 Hydrops fetalis due to isoimmunization (approximate)

Code annotations containing back-references to P56.0

Back-references to P56.0

• Type 1 Excludes: D56.0 Alpha thalassemia ("hydrops fetalis due to isoimmunization (P56.0)")

Back-references to P56

• Type 1 Excludes: K72 Hepatic failure, not elsewhere classified ("icterus of newborn (P55-P59)")
• Code Also: K76.82 Hepatic encephalopathy ("icterus of newborn (P55-P59)")
• Type 1 Excludes: P58 Neonatal jaundice due to other excessive hemolysis ("jaundice due to isoimmunization (P55-P57)")
• Type 1 Excludes: P83 Other conditions of integument specific to newborn ("hydrops fetalis due to hemolytic disease (P56.-)")

Diagnosis Index entries for P56.0

• Dropsy, dropsical › newborn due to isoimmunization
• Hydrops › fetalis › due to › ABO isoimmunization
• Hydrops › fetalis › due to › isoimmunization (ABO) (Rh)
• Hydrops › fetalis › due to › Rh incompatibility
• Hydrops › newborn (idiopathic) › due to › ABO isoimmunization
• Hydrops › newborn (idiopathic) › due to › isoimmunization (ABO) (Rh)
• Hydrops › newborn (idiopathic) › due to › Rh incompatibility
• Isoimmunization NEC › newborn › with › hydrops fetalis

Nearby codes

• P56 Hydrops fetalis due to hemolytic disease
• P56.0 Hydrops fetalis due to isoimmunization (this code)
• P56.9 Hydrops fetalis due to other and unspecified hemolytic disease
• P56.90 Hydrops fetalis due to unspecified hemolytic disease
• P56.99 Hydrops fetalis due to other hemolytic disease