2027 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 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

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 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 951. 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 the other POA exempt codes in Persons encountering health services in circumstances related to reproduction (Z30-Z39).

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to Z39.1: its own notes plus those printed at Chapter 21. A note printed at a category, block or chapter applies to every code under it.

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Encounter for supervision of lactation

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

  • disorders of lactation (O92.-)

Notes

General instructions on how these codes are used.

From Chapter 21 (Z00-Z99) Factors influencing health status and contact with health services applies to 1,425 codes
  • Z codes represent reasons for encounters. A corresponding procedure code must accompany a Z code if a procedure is performed. Categories Z00-Z99 are provided for occasions when circumstances other than a disease, injury or external cause classifiable to categories A00-Y89 are recorded as 'diagnoses' or 'problems'. This can arise in two main ways:
  • (a) When a person who may or may not be sick encounters the health services for some specific purpose, such as to receive limited care or service for a current condition, to donate an organ or tissue, to receive prophylactic vaccination (immunization), or to discuss a problem which is in itself not a disease or injury.
  • (b) When some circumstance or problem is present which influences the person's health status but is not in itself a current illness or injury.

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name Z39.1, its category, or a range that includes it.

Excludes2 1

These codes carry an Excludes2 note naming Z39.1: its condition is not part of those codes, and both may be reported when the patient has both.

  • Block Z00-Z13 Persons encountering health services for examinations
    examinations related to pregnancy and reproduction (Z30-Z36, Z39.-) names Z39.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About Z39.1Overview

What is the ICD-10 code for encounter for care and examination of lactating mother?

The ICD-10-CM code for encounter for care and examination of lactating mother is Z39.1 (sometimes written as Z391). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

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, 2026 through September 30, 2027.

What MS-DRG does Z39.1 group to?

On inpatient claims, encounter for care and examination of lactating mother maps to MS-DRG 951 (other Factors Influencing Health Status), which carries a relative weight of 0.5574. Higher weights mean higher Medicare reimbursement.

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.