ICD-10-CM 2027 diagnosis code
O10.413Pre-existing secondary hypertension complicating pregnancy, third trimester
O10.413 is a valid, billable ICD-10-CM code for pre-existing secondary hypertension complicating pregnancy, third trimester. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.Short description: Pre-existing secondary htn comp pregnancy, third trimester
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 O10.413
O10.413 is the ICD-10-CM diagnosis code for pre-existing secondary hypertension complicating pregnancy, third trimester. It belongs to category O10 (pre-existing hypertension complicating pregnancy, childbirth and the puerperium), block O10-O16 (edema, proteinuria and hypertensive disorders in pregnancy, childbirth and the puerperium) 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 O10.41 (pre-existing secondary hypertension complicating pregnancy), O10.413 is specifically for pre-existing secondary hypertension complicating pregnancy, third trimester. Related codes cover first trimester (O10.411), second trimester (O10.412) and unspecified trimester (O10.419).
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 642.11 (hypertension secondary to renal disease, complicating pregnancy, childbirth, and the puerperium, delivered, with or without mention of antepartum condition) and 642.13 (hypertension secondary to renal disease, complicating pregnancy, childbirth, and the puerperium, antepartum condition or complication).
Notes that apply from higher levels
Instructions written at a parent level also apply to O10.413.
› From O10.4 Pre-existing secondary hypertension complicating pregnancy, childbirth and the puerperium
- code from I15 to identify the type of secondary hypertension
› From O10 Pre-existing hypertension complicating pregnancy, childbirth and the puerperium
- pre-existing hypertension with pre-existing proteinuria complicating pregnancy, childbirth and the puerperium
- pre-existing hypertension with superimposed pre-eclampsia complicating pregnancy, childbirth and the puerperium (O11.-)
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.
MDC 14 · Pregnancy, Childbirth and the Puerperium
ICD-9-CM equivalent
Converter →- 642.11Hypertension secondary to renal disease, complicating pregnancy, childbirth, and the puerperium, delivered, with or without mention of antepartum conditionapproximate
- 642.13Hypertension secondary to renal disease, complicating pregnancy, childbirth, and the puerperium, antepartum condition or complicationapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about O10.413
Is O10.413 billable?
- Yes. O10.413 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can O10.413 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict O10.413 as a principal diagnosis.
Is O10.413 a CC or MCC?
- O10.413 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.
What DRG does O10.413 group to?
- O10.413 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 O10.413?
- The CMS General Equivalence Mappings map O10.413 to ICD-9-CM 642.11 and 642.13.