ICD-10 O24.313
Billable / Specific CCUnspecified pre-existing diabetes mellitus in pregnancy, third trimester
About ICD-10-CM O24.313
ICD-10-CM code O24.313 represents Unspecified pre-existing diabetes mellitus in pregnancy, third trimester. This is a billable/specific code in the Pregnancy, Childbirth, and Puerperium chapter (block O24). The 2026 edition of ICD-10-CM O24.313 became effective on October 1, 2025.
Coding Tips for O24.313
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
O24.313 is designated CC for MS-DRG grouping. On inpatient claims, this code can shift the DRG to the with-CC variant when documented as a present-on-admission secondary diagnosis. Hospital CDI programs flag CC opportunities during chart review. Failure to capture this code may leave 30 to 80 percent of the inpatient stay revenue unrealized.
Most O codes require a 7th character indicating trimester (1 = first, 2 = second, 3 = third). Some require fetus identification character. Code O09 (supervision of high-risk pregnancy) is required as a secondary code when applicable.
Inpatient DRG Impact, CC
codes Unspecified pre-existing diabetes mellitus in pregnancy, third trimester. As a Complication/Comorbidity (CC), this contributes to DRG severity adjustment when documented alongside the principal diagnosis.
Medicare LCD Coverage for O24.313
Local Coverage Determinations (LCDs) from CMS MACs that list O24.313 as a covered diagnosis.
Showing top 9. Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing O24.313.
3 Medicare
CPT Codes Commonly Billed with O24.313
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.
Convert O24.313 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| O24.313 | 64801 | 10000 |
| O24.313 | 64803 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To O24.313
Other codes in section O20-O29 (Other maternal disorders predominantly related to pregnancy).
ICD-10 O24.313, Billing FAQ
Is ICD-10 code O24.313 billable? +
Yes, O24.313 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
Is O24.313 a CC or MCC for inpatient DRG? +
Yes, this code is designated as CC. Documenting as a secondary diagnosis on inpatient claims can shift the DRG to a higher-weighted category.
What ICD-9 codes does O24.313 map to? +
Per CMS GEMs, O24.313 maps to ICD-9 codes: 64801, 64803. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
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