ICD-10-CM
ICD-10 code for Delay, delayed menstruation (cause unknown): N91.0
The ICD-10-CM index points "Delay, delayed menstruation (cause unknown)" to N91.0, Primary amenorrhea. N91.0 is a billable code.
Source: CDC ICD-10-CM FY2027 Alphabetic Index file dated June 16, 2026. Publisher page
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More specific codes in N91
A header groups codes and is not billed. A billable code is one you can report.
Excludes1
Excludes1 means these codes are not reported together.
From N91. A note on a category applies to every code under it.
Related conditions
Related pages
- N91.0 code detailsNotes, nearby codes, CMS-HCC group
- Category N91Every code under it
- Chapter 14Diseases of the genitourinary system
- ICD-10 codes by conditionA to Z
- Check a list of ICD-10 codes
- Denial code CO-11Diagnosis does not support the procedure
- Denial code CO-146Diagnosis invalid for the date of service
- HCPCS Level II code lookup
Questions
What is the ICD-10 code for Delay, delayed menstruation (cause unknown)?
The ICD-10-CM index points "Delay, delayed menstruation (cause unknown)" to N91.0, Primary amenorrhea. N91.0 is a billable code.
Is N91.0 billable?
Yes. N91.0 is a billable code in the FY2027 ICD-10-CM file. Use a more specific code when the record documents one.
What documentation notes apply to N91.0?
The CDC tabular list gives 1 Excludes1 note (not coded together) for N91.0 and the categories above it. They are listed on this page.
What chapter is N91.0 in?
Chapter 14. Diseases of the genitourinary system.
When do ICD-10-CM codes change?
Every October 1, with the new fiscal year file. Some years add April 1 updates. This page uses the FY2027 file, effective October 1, 2026.