2026 ICD-10-CM Diagnosis Code O98.119Syphilis complicating pregnancy, unspecified trimester

ICD-10-CM Codes›O00-O9A›O94-O9A›O98

ICD-10-CM O98.119
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

O98.119 is a billable ICD-10-CM diagnosis code for syphilis complicating pregnancy, unspecified trimester. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 817 through 819, 831 through 833. The code is restricted by the Medicare Code Editor to maternity cases (age 9 through 64). Coders also document this condition as maternal syphilis during pregnancy, childbirth and the puerperium. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified complications in pregnancy and Sexually transmitted infections (excluding HIV and hepatitis).

Code Identity

ICD-10-CM Code
O98.119
Billable Status
Yes — Valid for Submission
Code Describes
Syphilis complicating pregnancy, unspecified trimester
Short Description
Syphilis complicating pregnancy, unspecified trimester
Same as the full description in the CMS dataset.
Parent Code
O98.11
Syphilis complicating pregnancy

Code Classification

ChapterO00-O9APregnancy, childbirth and the puerperium
SectionO94-O9AOther obstetric conditions, not elsewhere classified
CategoryO98Maternal infectious and parasitic diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium
This CodeO98.119Syphilis complicating pregnancy, unspecified trimester

Code EditsBilling

Medicare Code Editor checks that affect claim validity for O98.119.

Maternity diagnoses
The Medicare Code Editor detects inconsistencies in maternity cases by checking a patient's age and any diagnosis on the patient's record. The maternity code edits apply to patients age ange is 9–64 years inclusive (e.g., diabetes in pregnancy, antepartum pulmonary complication).

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Maternal syphilis during pregnancy, childbirth and the puerperium

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR PRG028
Other specified complications in pregnancy
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR INF010
Sexually transmitted infections (excluding HIV and hepatitis)
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Infections and Pregnancy

During pregnancy, some common infections such as the common cold or a skin infection do not usually cause serious problems. Some infections, such as the flu, can be more severe when you're pregnant. But other infections can be harmful to you, your fetus, or both.

The full article covers:

  • How can infections affect your pregnancy?
  • What infections can be harmful during pregnancy?
  • What are the symptoms of an infection during pregnancy?
  • What are the treatments for infections during pregnancy?
  • Can infections during pregnancy be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert O98.119 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
647.00 Syphilis in preg-unspec
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About O98.119Overview

Is O98.119 (Syphilis complicating pregnancy) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report syphilis complicating pregnancy, unspecified trimester on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does O98.119 group to?

When syphilis complicating pregnancy, unspecified trimester is the principal diagnosis on an inpatient stay, it groups to MS-DRG 817, 818, 819, 831, 832, 833, with relative weights from 0.5229 to 1.6880 depending on complications. Higher weights mean higher Medicare reimbursement.

Who can O98.119 be reported for?

The Medicare Code Editor checks syphilis complicating pregnancy, unspecified trimester against patient demographics: this code is intended for maternity cases (age 9 through 64). Claims outside these limits are flagged as inconsistent.

What is the ICD-9 equivalent of O98.119?

Under the General Equivalence Mappings, syphilis complicating pregnancy, unspecified trimester converts to ICD-9-CM 647.00 (syphilis in preg-unspec). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.