2026 ICD-10-CM Diagnosis Code Z05.73Observation and evaluation of newborn for suspected connective tissue condition ruled out

ICD-10-CM Codes›Z00–Z99›Z00-Z13›Z05

ICD-10-CM Z05.73
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Z05.73 is a billable ICD-10-CM diagnosis code for observation and evaluation of newborn for suspected connective tissue condition ruled out. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). The code is restricted by the Medicare Code Editor to newborn patients (age 0) and exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Encounter for observation and examination for conditions ruled out (excludes infectious disease, neoplasm, mental disorders).

Code Identity

ICD-10-CM Code
Z05.73
Billable Status
Yes — Valid for Submission
Code Describes
Observation and evaluation of newborn for suspected connective tissue condition ruled out
Short Description
Obs & eval of NB for suspected conn tiss condition ruled out
Parent Code
Z05.7
Observation and evaluation of newborn for suspected skin, subcutaneous, musculoskeletal and connective tissue condition ruled out

Code Classification

ChapterZ00–Z99Factors influencing health status and contact with health services
SectionZ00-Z13Persons encountering health services for examinations
CategoryZ05Encounter for observation and evaluation of newborn for suspected diseases and conditions ruled out
This CodeZ05.73Observation and evaluation of newborn for suspected connective tissue condition ruled out

Code EditsBilling

Medicare Code Editor checks that affect claim validity for Z05.73.

Perinatal / Newborn diagnoses
The Medicare Code Editor detects inconsistencies in perinatal / newborn cases by checking a patient's age and any diagnosis on the patient's record. The newborn code edits apply to patients age 0 years only; a subset of diagnoses which will only occur during the perinatal or newborn period of age 0 (e.g., tetanus neonatorum, health examination for newborn under 8 days old).

Present on Admission (POA)Billing

Z05.73 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Observation(following) (for) (without need for further medical care)
      • newborn (for)
        • suspected condition, related to exposure from the mother or birth process
          • ruled out
            • connective tissue

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR FAC003
Encounter for observation and examination for conditions ruled out (excludes infectious disease, neoplasm, mental disorders)
Default principal diagnosis: inpatient Yes · outpatient Yes

Convert Z05.73 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
V29.8 NB obsrv oth suspct cond
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement Z05.73 replaces the following previously assigned code(s):

  • P00.89 - Newborn affected by oth maternal conditions
  • P00.89 - Newborn affected by other maternal conditions
FY 2018AddedAdded to the ICD-10-CM code setEffective October 1, 2017.
FY 2019–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Z05.73Overview

Is Z05.73 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report observation and evaluation of newborn for suspected connective tissue condition ruled out on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Who can Z05.73 be reported for?

The Medicare Code Editor checks observation and evaluation of newborn for suspected connective tissue condition ruled out against patient demographics: this code is intended for newborn patients (age 0). Claims outside these limits are flagged as inconsistent.

Is Z05.73 exempt from POA reporting?

Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for observation and evaluation of newborn for suspected connective tissue condition ruled out on inpatient claims.

What is the ICD-9 equivalent of Z05.73?

Under the General Equivalence Mappings, observation and evaluation of newborn for suspected connective tissue condition ruled out converts to ICD-9-CM V29.8 (NB obsrv oth suspct cond). The mapping is approximate, so confirm the match fits the documentation.