P03.819 Newborn affected by abnormality in fetal (intrauterine) heart rate or rhythm, unspecified as to time of onset

P03.819 is a billable/specific diagnosis code from the 2026 ICD-10-CM used to classify the following condition: Newborn affected by abnormality in fetal (intrauterine) heart rate or rhythm, unspecified as to time of onset.