2027 ICD-10-CM Diagnosis Code O30.029Conjoined twin pregnancy, unspecified trimester
ICD-10-CM Codes›O00-O9A›O30-O48›O30
- Billable — Valid for Submission
- Not Chronic
O30.029 is a billable ICD-10-CM diagnosis code for conjoined twin pregnancy, 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 conjoined twin pregnancy. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Multiple gestation.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for O30.029.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Conjoined twin pregnancy
- Disproportion between fetus and pelvis
- Disproportion between fetus and pelvis due to conjoined twins
- Fetal conjoined twins
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to O30.029: its own notes plus those printed at O30 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.
Code Also
A second code may be needed to fully describe the condition; the note gives no sequencing direction.
- any complications specific to multiple gestation
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 O30.029, its category, or a range that includes it.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Twin Pregnancy
a pregnancy involving two fetuses.
Patient EducationClinical
Twins, Triplets, Multiple Births
If you are pregnant with more than one baby, you are far from alone. Multiple births are up in the United States. More women are having babies after age 30 and more are taking fertility drugs. Both boost the chance of carrying more than one baby. A family history of twins also makes multiples more likely.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert O30.029 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About O30.029Overview
What is the ICD-10 code for conjoined twin pregnancy, unspecified trimester?
The ICD-10-CM code for conjoined twin pregnancy, unspecified trimester is O30.029 (sometimes written as O30029). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is O30.029 (Conjoined twin pregnancy) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report conjoined twin pregnancy, unspecified trimester on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does O30.029 group to?
When conjoined twin pregnancy, 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 O30.029 be reported for?
The Medicare Code Editor checks conjoined twin pregnancy, 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 O30.029?
Under the General Equivalence Mappings, conjoined twin pregnancy, unspecified trimester converts to ICD-9-CM 678.10 (fetal conjoin twins-unsp). The mapping is approximate, so confirm the match fits the documentation.
