N91

Absent, scanty and rare menstruation

FY2027Chapter 14: Diseases of the genitourinary system/N80–N98 Noninflammatory disorders of female genital tract

Non-billable headerNot valid on its own. Use one of the more specific codes under it.

N91 is a non-billable ICD-10-CM code category for absent, scanty and rare menstruation. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are N91.0 Primary amenorrhea; N91.1 Secondary amenorrhea; N91.2 Amenorrhea, unspecified; N91.3 Primary oligomenorrhea and 2 more. Its coding notes include 1 Excludes1 entry and 8 Excludes2 entries.

Excludes1

Not coded here. The listed conditions generally should not be reported together.

This code
  • ovarian dysfunction (E28.-)

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (8 notes)
Inherited from Chapter 14 Diseases of the genitourinary system
  • 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)

More specific codes under N91 6