2027 ICD-10-CM Diagnosis Code O33.0Maternal care for disproportion due to deformity of maternal pelvic bones
ICD-10-CM Codes›O00-O9A›O30-O48›O33
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Not Chronic
O33.0 is a billable ICD-10-CM diagnosis code for maternal care for disproportion due to deformity of maternal pelvic bones. 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. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 1 closely related codes. The code is restricted by the Medicare Code Editor to maternity cases (age 9 through 64). Coders also document this condition as disproportion - major pelvic abnormality. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Malposition, disproportion or other labor complications.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for O33.0.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Disproportion - major pelvic abnormality
- Fetal disorder due to pelvic size and disproportion during delivery
- Fetal disorder due to pelvic size and disproportion during labor
- Pelvis not adequate for delivery
- Problem of pelvis for delivery
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to O33.0: its own notes plus those printed at O33 and Chapter 15. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- the listed conditions as a reason for observation, hospitalization or other obstetric care of the mother, or for cesarean delivery before onset of labor
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Maternal care for disproportion due to pelvic deformity causing disproportion NOS
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 O33.0, its category, or a range that includes it.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Pregnancy (single) (uterine) See Also: Delivery and Puerperal; Z33.1
Rachitic See Also: condition;
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Childbirth Problems
Childbirth is the process of giving birth to a baby. It includes labor and delivery. Usually everything goes well, but problems can happen. They may cause a risk to the mother, baby, or both. Some of the more common childbirth problems include:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert O33.0 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About O33.0Overview
Is O33.0 (Maternal care for disproportion) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report maternal care for disproportion due to deformity of maternal pelvic bones on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does O33.0 group to?
When maternal care for disproportion due to deformity of maternal pelvic bones 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.
Is O33.0 a CC or MCC?
CMS lists O33.0 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 1 closely related codes in its exclusion list.
Who can O33.0 be reported for?
The Medicare Code Editor checks maternal care for disproportion due to deformity of maternal pelvic bones 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 O33.0?
Under the General Equivalence Mappings, maternal care for disproportion due to deformity of maternal pelvic bones converts to ICD-9-CM 648.71 (bone disorder-delivered), 648.72 (bone disorder-del w p/p), and 653.01 (pelvic deform NOS-deliv). The mapping is approximate, so confirm the match fits the documentation.
