N91.5 — Oligomenorrhea, unspecified
N91.5 is a billable, specific ICD-10-CM code for oligomenorrhea, unspecified. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Hypomenorrhea NOS
Other codes that can never be billed with N91.5
These codes carry an Excludes1 note pointing at N91.5. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading N91.5 alone.
- N92.6Irregular menstruation, unspecified
Risk adjustment
N91.5 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
How N91.5 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to N91.5.
- Oligomenorrhea
Related codes at this level
Codes that share N91. If N91.5 is not quite right, the correct code is usually one of these.
Questions about N91.5
- Is N91.5 a billable ICD-10-CM code?
- Yes. N91.5 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does N91.5 sit in the tabular list?
- Diseases of the genitourinary system (N00-N99), in the block Noninflammatory disorders of female genital tract (N80-N98).