P04 ICD-10-CM Code: Newborn affected by noxious substances transmitted via placenta or breast milk

P04 is the ICD-10-CM diagnosis code for newborn affected by noxious substances transmitted via placenta or breast milk. P04 sits in the ICD-10-CM chapter for certain conditions originating in the perinatal period (p00-p96), within the section covering newborn affected by maternal factors and by complications of pregnancy, labor, and delivery (p00-p04).

Header codes like P04 cannot be reported on claims directly, they organize child codes that share clinical context but the actual diagnosis must be coded to the highest level of specificity supported by the documentation. Coders should look at P04's child codes and select the one that matches the patient's documented presentation, since payers reject header codes submitted as the primary diagnosis. For risk adjustment workflows, header codes never contribute to a Medicare Advantage member's RAF score on their own; only billable child codes that happen to map to a payment HCC affect risk-adjusted plan payments.