2027 ICD-10-CM Diagnosis Code O26.50Maternal hypotension syndrome, unspecified trimester
ICD-10-CM Codes›O00-O9A›O20-O29›O26
- Billable — Valid for Submission
- Not Chronic
O26.50 is a billable ICD-10-CM diagnosis code for maternal hypotension syndrome, unspecified trimester. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) 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 hypotension syndrome. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Hypotension and Other specified complications in pregnancy.
This medical diagnosis code is frequently used in OB/GYN medical specialties to designate conditions such maternal disorders related to pregnancy.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for O26.50.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Maternal hypotension syndrome
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to O26.50: its own notes plus those printed at block O20-O29 and Chapter 15. A note printed at a category, block or chapter applies to every code under it.
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
- supervision of normal pregnancy (Z34.-)
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Use Additional Code
Add a second code, after this one, to fully describe the condition.
- code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.
Notes
General instructions on how these codes are used.
- CODES FROM THIS CHAPTER ARE FOR USE ONLY ON MATERNAL RECORDS, NEVER ON NEWBORN RECORDS
- Codes from this chapter are for use for conditions related to or aggravated by the pregnancy, childbirth, or by the puerperium (maternal causes or obstetric causes)
- Trimesters are counted from the first day of the last menstrual period. They are defined as follows:
- 1st trimester- less than 14 weeks 0 days
- 2nd trimester- 14 weeks 0 days to less than 28 weeks 0 days
- 3rd trimester- 28 weeks 0 days until delivery
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name O26.50, its category, or a range that includes it.
Excludes1 3
These codes carry an Excludes1 note naming O26.50: they are not reported together with it, unless the two conditions are unrelated.
- I95 Hypotensionmaternal hypotension syndrome (O26.5-) names O26.5-, which includes this code
- R03.1 Nonspecific low blood-pressure readingmaternal hypotension syndrome (O26.5-) names O26.5-, which includes this code
- Z03.7 Encounter for suspected maternal and fetal conditions ruled outknown or suspected fetal anomalies affecting management of mother, not ruled out (O26.-, O35.-, O36.-, O40.-, O41.-) names O26.-, which includes this code
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Health Problems in Pregnancy
A health problem in pregnancy is any disease or condition that could affect your health or the health of your fetus. Some health problems may make it more likely that you will have a high-risk pregnancy. A high-risk pregnancy is one in which you, your fetus, or both are at higher risk for health problems than in a typical pregnancy.
The full article covers:
- What are health problems in pregnancy?
- What raises my risk for health problems during pregnancy?
- Can chronic health conditions cause problems in pregnancy?
- Can health problems in pregnancy be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert O26.50 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About O26.50Overview
What is the ICD-10 code for maternal hypotension syndrome, unspecified trimester?
The ICD-10-CM code for maternal hypotension syndrome, unspecified trimester is O26.50 (sometimes written as O2650). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is O26.50 (Maternal hypotension syndrome) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report maternal hypotension syndrome, unspecified trimester on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does O26.50 group to?
When maternal hypotension syndrome, unspecified trimester is the principal diagnosis on an inpatient stay, it groups to MS-DRG 833, 832, 831, 819, 818, 817, with relative weights from 0.5000 to 1.7586 depending on complications. Higher weights mean higher Medicare reimbursement.
Who can O26.50 be reported for?
The Medicare Code Editor checks maternal hypotension syndrome, 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 O26.50?
Under the General Equivalence Mappings, maternal hypotension syndrome, unspecified trimester converts to ICD-9-CM 669.20 (matern hypotens syn-unsp). The mapping is approximate, so confirm the match fits the documentation.
