Skip to content
Dx

ICD-10-CM 2027 diagnosis code

O98.613Protozoal diseases complicating pregnancy, third trimester

✓ Billable / specificCC — complication/comorbidityMaternity · age 9–64Female only

O98.613 is a valid, billable ICD-10-CM code for protozoal diseases complicating pregnancy, third trimester. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About O98.613

O98.613 is the ICD-10-CM diagnosis code for protozoal diseases complicating pregnancy, third trimester. It belongs to category O98 (maternal infectious and parasitic diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium), block O94-O9A (other obstetric conditions, not elsewhere classified) and chapter 15 (pregnancy, childbirth and the puerperium). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within O98.61 (protozoal diseases complicating pregnancy), O98.613 is specifically for protozoal diseases complicating pregnancy, third trimester. Related codes cover first trimester (O98.611), second trimester (O98.612) and unspecified trimester (O98.619).

Use an additional code (Chapter 1), to identify specific infectious or parasitic disease.

As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 817 (Other Antepartum Diagnoses with O.R. Procedures with MCC, relative weight 2.0534), DRG 818 (Other Antepartum Diagnoses with O.R. Procedures with CC, relative weight 1.2942), DRG 819 (Other Antepartum Diagnoses with O.R. Procedures without CC/MCC, relative weight 0.7739), DRG 831 (Other Antepartum Diagnoses without O.R. Procedures with MCC, relative weight 1.1558), DRG 832 (Other Antepartum Diagnoses without O.R. Procedures with CC, relative weight 0.7585) and DRG 833 (Other Antepartum Diagnoses without O.R. Procedures without CC/MCC, relative weight 0.5002), in MDC 14 (Pregnancy, Childbirth and the Puerperium), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

The Medicare Code Editor treats this as a maternity diagnosis, expected only for patients age 9 through 64.

It is on the CMS list of diagnoses consistent only with female patients (the sex-conflict edit itself was retired in FY2025).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 647.81 (other specified infectious and parasitic diseases of mother, delivered, with or without mention of antepartum condition) and 647.83 (other specified infectious and parasitic diseases of mother, antepartum condition or complication).

Notes that apply from higher levels

Instructions written at a parent level also apply to O98.613.

› 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
  • 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

Broader instructions also apply from Chapter 15: Pregnancy, childbirth and the puerperium.

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

ICD-9-CM equivalent

Converter →
  • 647.81Other specified infectious and parasitic diseases of mother, delivered, with or without mention of antepartum conditionapproximate
  • 647.83Other specified infectious and parasitic diseases of mother, antepartum condition or complicationapproximate

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about O98.613

Is O98.613 billable?

Yes. O98.613 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can O98.613 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict O98.613 as a principal diagnosis.

Is O98.613 a CC or MCC?

O98.613 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.

What DRG does O98.613 group to?

O98.613 is used in the MS-DRG v44.0 logic for MS-DRG 817 (Other Antepartum Diagnoses with O.R. Procedures with MCC), MS-DRG 818 (Other Antepartum Diagnoses with O.R. Procedures with CC), MS-DRG 819 (Other Antepartum Diagnoses with O.R. Procedures without CC/MCC), MS-DRG 831 (Other Antepartum Diagnoses without O.R. Procedures with MCC), MS-DRG 832 (Other Antepartum Diagnoses without O.R. Procedures with CC) and MS-DRG 833 (Other Antepartum Diagnoses without O.R. Procedures without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for O98.613?

The CMS General Equivalence Mappings map O98.613 to ICD-9-CM 647.81 and 647.83.