O99.111 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, first trimester

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applies from O99 Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium

Includes

• conditions which complicate the pregnant state, are aggravated by the pregnancy or are a main reason for obstetric care

Excludes2 (not included here)

• when the reason for maternal care is that the condition is known or suspected to have affected the fetus (O35-O36)

Use additional code

• code to identify specific condition

Applies from O99.1 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, childbirth and the puerperium

Applicable to

• Conditions in D65-D89

Excludes1 (never code together)

• hemorrhage with coagulation defects (O45.-, O46.0-, O67.0, O72.3)

MS-DRG index

Defines the logic of DRG(s) 817-819 in MDC 14.

Approximate ICD-9-CM (GEMs)

• 649.31 Coagulation defects complicating pregnancy, childbirth, or the puerperium, delivered, with or without mention of antepartum condition (approximate)
• 649.33 Coagulation defects complicating pregnancy, childbirth, or the puerperium, antepartum condition or complication (approximate)

Medicare Code Edits (MCE v43.1 (April 2026))

• Maternity diagnoses (age 9 through 64): Age conflict edit. These diagnoses are clinically expected only in patients age 9 through 64.

Nearby codes

• O99.019 Anemia complicating pregnancy, unspecified trimester
• O99.02 Anemia complicating childbirth
• O99.03 Anemia complicating the puerperium
• O99.1 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, childbirth and the puerperium
• O99.11 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy
• O99.111 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, first trimester (this code)
• O99.112 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, second trimester
• O99.113 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, third trimester
• O99.119 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating pregnancy, unspecified trimester
• O99.12 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating childbirth
• O99.13 Other diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism complicating the puerperium