2027 ICD-10-CM Diagnosis Code N80.9Endometriosis, unspecified

ICD-10-CM Codes›N00–N99›N80-N98›N80

ICD-10-CM N80.9
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

N80.9 is a billable ICD-10-CM diagnosis code for endometriosis, unspecified. 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, 760 through 761. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Endometriosis.

Code Identity

ICD-10-CM Code
N80.9
Billable Status
Yes — Valid for Submission
Code Describes
Endometriosis, unspecified
Short Description
Endometriosis, unspecified
Same as the full description in the CMS dataset.
Parent Code
N80
Endometriosis

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN80-N98Noninflammatory disorders of female genital tract
CategoryN80Endometriosis
This CodeN80.9Endometriosis, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Adhesions due to endometriosis
  • Adhesions of rectovaginal pouch due to endometriosis
  • Adnexal adhesions due to endometriosis
  • Deciduomatosis
  • Dense adhesions of rectovaginal pouch due to endometriosis
  • Dense adnexal adhesions due to endometriosis
  • Endometriosis
  • Endometriosis of pelvis
  • Female infertility due to endometriosis
  • Female pelvic peritoneal adhesions
  • Filmy adhesions of rectovaginal pouch due to endometriosis
  • Filmy uterine adnexal adhesions due to endometriosis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to N80.9: its own notes plus those printed at Chapter 14. A note printed at a category, block or chapter applies to every code under it.

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 Chapter 14 (N00-N99) Diseases of the genitourinary system applies to 838 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name N80.9, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming N80.9: they are not reported together with it, unless the two conditions are unrelated.

  • N85 Other noninflammatory disorders of uterus, except cervix
    endometriosis (N80.-) names N80.-, 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 GEN019
Endometriosis
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Endometriosis

    a condition in which functional endometrial tissue is present outside the uterus. it is often confined to the pelvis involving the ovary, the ligaments, cul-de-sac, and the uterovesical peritoneum.

Patient EducationClinical

Endometriosis

The uterus, or womb, is the place where a fetus grows during pregnancy. The uterus is lined with tissue (endometrium). Endometriosis is a disease in which tissue like the lining of the uterus grows in other places in your body. These patches of tissue are called "implants," "nodules," or "lesions." They are most often found:

The full article covers:

  • What is endometriosis?
  • What causes endometriosis?
  • Who is at risk for endometriosis?
  • What are the symptoms of endometriosis?
  • How is endometriosis diagnosed?
  • What are the treatments for endometriosis?

Read the full article at MedlinePlus

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

Convert N80.9 to ICD-9-CMHistory

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

ICD-9-CM
617.9 Endometriosis NOS
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 N80.9Overview

What is the ICD-10 code for endometriosis, unspecified?

The ICD-10-CM code for endometriosis, unspecified is N80.9 (sometimes written as N809). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is N80.9 (Endometriosis) a billable code?

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

What MS-DRG does N80.9 group to?

When endometriosis, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 742, 743, 760, 761, with relative weights from 0.7039 to 1.8448 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of N80.9?

Under the General Equivalence Mappings, endometriosis, unspecified converts to ICD-9-CM 617.9 (endometriosis NOS). The mapping is a direct match.