2027 ICD-10-CM Diagnosis Code N91Absent, scanty and rare menstruation

ICD-10-CM Codes›N00–N99›N80-N98›N91

ICD-10-CM N91
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

N91 is a non-billable ICD-10-CM category code for absent, scanty and rare menstruation, so it cannot be submitted on claims. Use a more specific code from this category instead, such as N91.0, N91.1, N91.2, and N91.3.

Code Identity

ICD-10-CM Code
N91
Billable Status
No — Non-Billable Category
Code Describes
Absent, scanty and rare menstruation
Short Description
Absent, scanty and rare menstruation
Same as the full description in the CMS dataset.
Chapter
N80-N98
Noninflammatory disorders of female genital tract

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN80-N98Noninflammatory disorders of female genital tract
CategoryN91Absent, scanty and rare menstruation
This CodeN91Absent, scanty and rare menstruation

Specific Coding for Absent, scanty and rare menstruationOverview

Non-specific codes like N91 require more characters. Use one of these billable codes instead:

  • Use N91.0 for Primary amenorrhea

  • Use N91.1 for Secondary amenorrhea

  • Use N91.2 for Amenorrhea, unspecified

  • Use N91.3 for Primary oligomenorrhea

  • Use N91.4 for Secondary oligomenorrhea

  • Use N91.5 for Oligomenorrhea, unspecified

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to N91: its own notes plus those printed at Chapter 14. A note printed at a category, block or chapter applies to every code under it.

Excludes1

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

  • ovarian dysfunction (E28.-)

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.

Patient EducationClinical

Menstruation

Menstruation, also called a period, is normal vaginal bleeding that happens as part of the monthly cycle in women and girls. Every month, the body prepares for pregnancy. If pregnancy does not happen, the uterus (womb) sheds its lining. This blood and tissue leave the body through the vagina.

The full article covers:

  • What is menstruation?
  • What is the menstrual cycle?
  • When will my period start?
  • What are the symptoms of menstruation?
  • What are menstrual irregularities?

Read the full article at MedlinePlus

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

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 N91Overview

What is the ICD-10 code for absent, scanty and rare menstruation?

N91 is the ICD-10-CM category for absent, scanty and rare menstruation, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is N91 (Absent, scanty and rare menstruation) a billable code?

No. This is a category header that groups the codes for absent, scanty and rare menstruation, and headers cannot be submitted on claims. Claims for absent, scanty and rare menstruation need a more specific code from this category, such as N91.0, N91.1, and N91.2.

Can N91 be reported with a code from E28?

Not as a rule. The Excludes1 note on N91 lists "ovarian dysfunction (E28.-)". 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).