2027 ICD-10-CM Diagnosis Code A56.02Chlamydial vulvovaginitis

ICD-10-CM Codes›A00–B99›A50-A64›A56

ICD-10-CM A56.02
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A56.02 is a billable ICD-10-CM diagnosis code for chlamydial vulvovaginitis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 742 through 743, 757 through 759. Coders also document this condition as bacterial vaginosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Inflammatory diseases of female pelvic organs and Sexually transmitted infections (excluding HIV and hepatitis).

Code Identity

ICD-10-CM Code
A56.02
Billable Status
Yes — Valid for Submission
Code Describes
Chlamydial vulvovaginitis
Short Description
Chlamydial vulvovaginitis
Same as the full description in the CMS dataset.
Parent Code
Chlamydial infection of lower genitourinary tract

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA50-A64Infections with a predominantly sexual mode of transmission
CategoryA56Other sexually transmitted chlamydial diseases
This CodeA56.02Chlamydial vulvovaginitis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bacterial vaginosis
  • Chlamydia trachomatis infection of genital structure
  • Chlamydial pelvic inflammatory disease
  • Chlamydial vulvovaginitis
  • Infection of vagina caused by Chlamydia trachomatis
  • Infection of vulva caused by Chlamydia trachomatis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A56.02: its own notes plus those printed at A56, block A50-A64, and Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From A56 Other sexually transmitted chlamydial diseases applies to 10 codes
  • sexually transmitted diseases due to Chlamydia
  • trachomatis
From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Excludes1

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

From A56 Other sexually transmitted chlamydial diseases applies to 10 codes
  • neonatal chlamydial conjunctivitis (P39.1)
  • neonatal chlamydial pneumonia (P23.1)
From Block A50-A64 Infections with a predominantly sexual mode of transmission applies to 142 codes
  • nonspecific and nongonococcal urethritis (N34.1)
  • Reiter's disease (M02.3-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From A56 Other sexually transmitted chlamydial diseases applies to 10 codes
  • chlamydial lymphogranuloma (A55)
  • conditions classified to A74.-
From Block A50-A64 Infections with a predominantly sexual mode of transmission applies to 142 codes
  • human immunodeficiency virus [HIV] disease (B20)
From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name A56.02, its category, or a range that includes it.

Applicable To 1

These notes mention A56.02.

  • O98.3 Other infections with a predominantly sexual mode of transmission complicating pregnancy, childbirth and the puerperium
    Conditions in A55-A64 names A55-A64, which includes this code

Excludes1 4

These codes carry an Excludes1 note naming A56.02: they are not reported together with it, unless the two conditions are unrelated.

  • N74 Female pelvic inflammatory disorders in diseases classified elsewhere
    chlamydial cervicitis (A56.02)
  • N77.1 Vaginitis, vulvitis and vulvovaginitis in diseases classified elsewhere
    chlamydial vulvovaginitis (A56.02)
  • Block A70-A74 Other diseases caused by chlamydiae
    sexually transmitted chlamydial diseases (A55-A56) names A55-A56, which includes this code
  • A74 Other diseases caused by chlamydiae
    sexually transmitted chlamydial diseases (A55-A56) names A55-A56, which includes this code

Index to Diseases and InjuriesGuidance

Clinical ClassificationClinical

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

CCSR GEN018
Inflammatory diseases of female pelvic organs
Default principal diagnosis: inpatient No · outpatient No
CCSR INF010
Sexually transmitted infections (excluding HIV and hepatitis)
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Chlamydia Infections

Chlamydia is a common sexually transmitted infection (STI). It is caused by bacteria called Chlamydia trachomatis. Anyone can get chlamydia. It often doesn't cause symptoms, so people may not know that they have it. Antibiotics can cure it. But if it's not treated, chlamydia can cause serious health problems.

The full article covers:

  • What is chlamydia?
  • How is chlamydia spread?
  • Who is more likely to get chlamydia?
  • What are the symptoms of chlamydia?
  • How is chlamydia diagnosed?
  • Who should be tested for chlamydia?
  • What other problems can chlamydia cause?
  • What are the treatments for chlamydia?

Read the full article at MedlinePlus

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

Convert A56.02 to ICD-9-CMHistory

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

ICD-9-CM
099.53 Oth VD chlm trch lowr gu
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.
ICD-9-CM
616.11 Vaginitis in oth disease
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.

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 A56.02Overview

What is the ICD-10 code for chlamydial vulvovaginitis?

The ICD-10-CM code for chlamydial vulvovaginitis is A56.02 (sometimes written as A5602). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is A56.02 (Chlamydial infection of lower genitourinary tract) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report chlamydial vulvovaginitis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does A56.02 group to?

When chlamydial vulvovaginitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 742, 759, 743, 758, 757, with relative weights from 0.7687 to 1.8448 depending on complications. Higher weights mean higher Medicare reimbursement.

Can A56.02 be reported with P39.1?

Not as a rule. The Excludes1 note at A56, which applies to A56.02, lists "neonatal chlamydial conjunctivitis (P39.1)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What is the ICD-9 equivalent of A56.02?

Under the General Equivalence Mappings, chlamydial vulvovaginitis converts to ICD-9-CM 099.53 (oth VD chlm trch lowr gu) and 616.11 (vaginitis in oth disease). The mapping is approximate, so confirm the match fits the documentation.