ICD10

ICD-10 Code O99.1: Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, childbirth and the puerperium

O99.1 is an ICD-10 diagnosis entry used to group records related to Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, childbirth and the puerperium. You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen. ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Pregnancy, childbirth and the puerperium (O00-O9A).

Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026

What is this code?

ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Pregnancy, childbirth and the puerperium (O00-O9A).

When is it used?

  • May be used when a clinician documents other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, childbirth and the puerperium in a patient's medical record.
  • May appear in hospital records, claims, referrals, and clinical documentation.
  • This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.

What it does not mean

  • A code alone does not explain severity, treatment plan, or outcome.
  • A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
  • This entry may represent a broader category rather than the most specific billable code.

Code hierarchy

chapter
15Pregnancy, childbirth and the puerperium (O00-O9A)
block
O94-O9AOther obstetric conditions, not elsewhere classified
category
O99Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium
currentO99

Official coding notes

Inclusion terms
  • Conditions in D65-D89
Excludes1 (do not code together)
  • hemorrhage with coagulation defects (O45.-, O46.0-, O67.0, O72.3)

Where you may see this code

You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.

Related specialists

ObstetricianGynecologistHematologist

Related procedures

Obstetric ultrasound
May appear in pregnancy follow-up pathways when maternal diseases complicate pregnancy and fetal well-being is monitored.
Fetal nonstress testing
May be used in selected higher-risk pregnancy monitoring pathways.

Coding guidelines

Compatibility

Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.
Legacy codes
O99.1
Replacement codes
O99.12 — Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating childbirthO99.13 — Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating the puerperium

Common synonyms

Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, childbirth and the puerperium

Frequently asked questions

Code details

CodeO99.1
SystemICD10
Display nameOther diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, childbirth and the puerperium
ChapterPregnancy, childbirth and the puerperium (O00-O9A)
BlockOther obstetric conditions, not elsewhere classified

Flags

BillableNo
Valid clinical useNo

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.