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ICD-10-CM 2027 diagnosis code

Q91.3Trisomy 18, unspecified

✓ Billable / specificPOA exemptCC — complication/comorbidity

Q91.3 is a valid, billable ICD-10-CM code for trisomy 18, unspecified. 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 Q91.3

Q91.3 is the ICD-10-CM diagnosis code for trisomy 18, unspecified. It belongs to category Q91 (trisomy 18 and Trisomy 13), block Q90-Q99 (chromosomal abnormalities, not elsewhere classified) and chapter 17 (congenital malformations, deformations, chromosomal abnormalities, and genetic disorders). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within Q91, choose Q91.3 (18, unspecified) only when documentation doesn't support a more specific option: 18, nonmosaicism (meiotic nondisjunction) (Q91.0), 18, mosaicism (mitotic nondisjunction) (Q91.1), 18, translocation (Q91.2), 13, nonmosaicism (meiotic nondisjunction) (Q91.4), 13, mosaicism (mitotic nondisjunction) (Q91.5), 13, translocation (Q91.6) and 13, unspecified (Q91.7).

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 884 (Organic Disturbances and Intellectual Disability, relative weight 1.6001), in MDC 19 (Mental Diseases and Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It is exempt from present-on-admission (POA) reporting, so no POA indicator is required.

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 758.2 (Edwards' syndrome).

Notes that apply from higher levels

Instructions written at a parent level also apply to Q91.3.

Broader instructions also apply from Q90-Q99 Chromosomal abnormalities, not elsewhere classified and Chapter 17: Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders.

Alphabetic index entries

2 entries

Terms in the official ICD-10-CM index that lead to Q91.3.

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 →
  • 758.2Edwards' syndromeapproximate

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 Q91.3

Is Q91.3 billable?

Yes. Q91.3 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can Q91.3 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict Q91.3 as a principal diagnosis.

Is Q91.3 a CC or MCC?

Q91.3 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.

What DRG does Q91.3 group to?

Q91.3 is used in the MS-DRG v44.0 logic for MS-DRG 884 (Organic Disturbances and Intellectual Disability). 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 Q91.3?

The CMS General Equivalence Mappings map Q91.3 to ICD-9-CM 758.2.