2026 ICD-10-CM Diagnosis Code Z39.1Encounter for care and examination of lactating mother

ICD-10-CM Codes›Z00–Z99›Z30-Z39›Z39

ICD-10-CM Z39.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Z39.1 is a billable ICD-10-CM diagnosis code for encounter for care and examination of lactating mother. 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 maternity cases (age 9 through 64), not accepted as a principal diagnosis, and exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Uncomplicated pregnancy, delivery or puerperium.

Code Identity

ICD-10-CM Code
Z39.1
Billable Status
Yes — Valid for Submission
Code Describes
Encounter for care and examination of lactating mother
Short Description
Encounter for care and examination of lactating mother
Same as the full description in the CMS dataset.
Parent Code
Z39
Encounter for maternal postpartum care and examination

Code Classification

ChapterZ00–Z99Factors influencing health status and contact with health services
SectionZ30-Z39Persons encountering health services in circumstances related to reproduction
CategoryZ39Encounter for maternal postpartum care and examination
This CodeZ39.1Encounter for care and examination of lactating mother

Code EditsBilling

Medicare Code Editor checks that affect claim validity for Z39.1.

Maternity diagnoses
The Medicare Code Editor detects inconsistencies in maternity cases by checking a patient's age and any diagnosis on the patient's record. The maternity code edits apply to patients age ange is 9–64 years inclusive (e.g., diabetes in pregnancy, antepartum pulmonary complication).
Unacceptable principal diagnosis
There are selected codes that describe a circumstance which influences an individual's health status but not a current illness or injury, or codes that are not specific manifestations but may be due to an underlying cause. These codes are considered unacceptable as a principal diagnosis.

Present on Admission (POA)Billing

Z39.1 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Encounter for supervision of lactation

Type 1 Excludes

  • disorders of lactation O92

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.

    • Care(of) (for) (following)
      • lactating mother
    • Examination(for) (following) (general) (of) (routine)
      • lactating mother
    • Lactation, lactating(breast) (puerperal, postpartum)
      • mother (care and/or examination)
    • Supervision(of)
      • lactation

Clinical ClassificationClinical

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

CCSR PRG029
Uncomplicated pregnancy, delivery or puerperium
Default principal diagnosis: inpatient No · outpatient Yes

Patient EducationClinical

Breastfeeding

Breastfeeding offers many benefits to your baby. Breast milk contains the right balance of nutrients to help your infant grow into a strong and healthy toddler. Some of the nutrients in breast milk also help protect your infant against some common childhood illnesses and infections. It may also help your health.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert Z39.1 to ICD-9-CMHistory

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

ICD-9-CM
V24.1 Postpart care-lactation
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Z39.1Overview

Is Z39.1 (Encounter for maternal postpartum care and examination) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report encounter for care and examination of lactating mother on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Can Z39.1 be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because encounter for care and examination of lactating mother describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.

Who can Z39.1 be reported for?

The Medicare Code Editor checks encounter for care and examination of lactating mother against patient demographics: this code is intended for maternity cases (age 9 through 64). Claims outside these limits are flagged as inconsistent.

Is Z39.1 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 encounter for care and examination of lactating mother on inpatient claims.

What is the ICD-9 equivalent of Z39.1?

Under the General Equivalence Mappings, encounter for care and examination of lactating mother converts to ICD-9-CM V24.1 (postpart care-lactation). The mapping is a direct match.