2026 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 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

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

Tabular List NotesGuidance

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

Type 1 Excludes

  • ovarian dysfunction E28

Patient EducationClinical

Menstruation

Menstruation, or period, is normal vaginal bleeding that occurs as part of a woman's monthly cycle. Every month, your body prepares for pregnancy. If no pregnancy occurs, the uterus, or womb, sheds its lining. The menstrual blood is partly blood and partly tissue from inside the uterus. It passes out of the body through the vagina.

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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About N91Overview

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.