O98.511 Other viral diseases complicating pregnancy, first trimester

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

Applies from O98 Maternal infectious and parasitic diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium

Includes

• the listed conditions when complicating the pregnant state, when aggravated by the pregnancy, or as a reason for obstetric care

Excludes2 (not included here)

• herpes gestationis (O26.4-)
• infectious carrier state (O99.82-, O99.83-)
• obstetrical tetanus (A34)
• puerperal infection (O86.-)
• puerperal sepsis (O85)
• when the reason for maternal care is that the disease is known or suspected to have affected the fetus (O35-O36)

Use additional code

• code (Chapter 1), to identify specific infectious or parasitic disease

Applies from O98.5 Other viral diseases complicating pregnancy, childbirth and the puerperium

Applicable to

• Conditions in A80-B09, B25-B34, R87.81-, R87.82-

Excludes1 (never code together)

• human immunodeficiency virus [HIV] disease complicating pregnancy, childbirth and the puerperium (O98.7-)

MS-DRG index

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

Approximate ICD-9-CM (GEMs)

• 647.61 Other viral diseases in the mother, delivered, with or without mention of antepartum condition (approximate)
• 647.63 Other viral diseases in the mother, 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

• O98.419 Viral hepatitis complicating pregnancy, unspecified trimester
• O98.42 Viral hepatitis complicating childbirth
• O98.43 Viral hepatitis complicating the puerperium
• O98.5 Other viral diseases complicating pregnancy, childbirth and the puerperium
• O98.51 Other viral diseases complicating pregnancy
• O98.511 Other viral diseases complicating pregnancy, first trimester (this code)
• O98.512 Other viral diseases complicating pregnancy, second trimester
• O98.513 Other viral diseases complicating pregnancy, third trimester
• O98.519 Other viral diseases complicating pregnancy, unspecified trimester
• O98.52 Other viral diseases complicating childbirth
• O98.53 Other viral diseases complicating the puerperium