P08.21 Post-term newborn
The ICD-10-CM code for Post-term newborn is P08.21 (FY2026). It is a billable, claim-ready diagnosis code.
Classification
- Section
- P05-P08: Disorders of newborn related to length of gestation and fetal growth (P05-P08)
- Category P08
- 6 codes (4 billable)
- FY2026 Status
- Stable since FY2024
Also Known As
ICD-10-CM Alphabetic Index entries that lead to P08.21:
- Newborn (infant) (liveborn) (singleton) › post-term
- Post-term (40-42 weeks) (pregnancy) (mother) › infant
Inclusion Terms
- Newborn with gestation period over 40 completed weeks to 42 completed weeks
U.S. Hospital Utilization
- An estimated 190,875 U.S. inpatient stays in 2023 included P08.21 among the documented diagnoses.
- 160 stays listed it as the principal diagnosis.
Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.
Official Coding Guidelines
Use of Z05 codes (newborn suspected condition ruled out)1) Use of Z05 codes Assign a code from category Z05, Observation and evaluation of newborn for suspected diseases and conditions ruled out, to identify those instances when a healthy newborn is evaluated for a suspected condition/disease that is determined after study not to be present. Do not use a code from category Z05 when the patient is documented to have signs or symptoms of a suspected problem; in such cases code the sign or symptom.
Z05 on other than the birth record2) Z05 on other than the birth record A code from category Z05 may also be assigned as a principal or first- listed code for readmissions or encounters when the code from category Z38 code no longer applies. Codes from category Z05 are for use only for healthy newborns and infants for which no condition after study is found to be present.
Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026