2027 ICD-10-CM Diagnosis Code O29.3X9Toxic reaction to local anesthesia during pregnancy, unspecified trimester
ICD-10-CM Codes›O00-O9A›O20-O29›O29
- Billable — Valid for Submission
- Not Chronic
O29.3X9 is a billable ICD-10-CM diagnosis code for toxic reaction to local anesthesia during 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 obstetric toxic reaction to local anesthesia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Anesthesia complications during 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 O29.3X9.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Obstetric toxic reaction to local anesthesia
- Problem encountered during administration of local anesthetic
- Toxic reaction to local anesthesia during pregnancy
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to O29.3X9: its own notes plus those printed at O29, block O20-O29, 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.
- maternal complications arising from the administration of a general, regional or local anesthetic, analgesic or other sedation during pregnancy
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 necessary, to identify the complication
- 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 O29.3X9, its category, or a range that includes it.
Excludes1 4
These codes carry an Excludes1 note naming O29.3X9: they are not reported together with it, unless the two conditions are unrelated.
- J95.4 Chemical pneumonitis due to anesthesiaaspiration pneumonitis due to anesthesia complicating pregnancy (O29) names O29, which includes this code
- Block T36-T50 Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substancestoxic reaction to local anesthesia in pregnancy (O29.3-) names O29.3-, which includes this code
- T41 Poisoning by, adverse effect of and underdosing of anesthetics and therapeutic gasescomplications of anesthesia during pregnancy (O29.-) names O29.-, which includes this code
- T88.2 Shock due to anesthesiapregnancy (O29.-) names O29.-, which includes this code
Excludes2 3
These codes carry an Excludes2 note naming O29.3X9: its condition is not part of those codes, and both may be reported when the patient has both.
- J12 Viral pneumonia, not elsewhere classifiedaspiration pneumonia due to anesthesia during pregnancy (O29) names O29, which includes this code
- J18 Pneumonia, unspecified organismaspiration pneumonia due to anesthesia during pregnancy (O29) names O29, which includes this code
- T88 Other complications of surgical and medical care, not elsewhere classifiedcomplications of anesthesia in pregnancy (O29.-) names O29.-, which includes this code
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Anesthesia
Anesthesia is the use of medicines, called anesthetics, to prevent pain during surgery and other medical procedures. Medicine may be given by injection, inhalation, topical lotion, spray, eye drops, or a skin patch.
The full article covers:
- What is anesthesia?
- What is anesthesia used for?
- What are the types of anesthesia?
- What are the risks of anesthesia?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert O29.3X9 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About O29.3X9Overview
Is O29.3X9 (Toxic reaction to local anesthesia during pregnancy) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report toxic reaction to local anesthesia during pregnancy, unspecified trimester on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does O29.3X9 group to?
When toxic reaction to local anesthesia during 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 O29.3X9 be reported for?
The Medicare Code Editor checks toxic reaction to local anesthesia during 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.
Does O29.3X9 need an additional code?
When the condition applies, yes. The Use Additional Code note at O29, which applies to O29.3X9, reads: code, if necessary, to identify the complication. The additional code is reported after O29.3X9.
What is the ICD-9 equivalent of O29.3X9?
Under the General Equivalence Mappings, toxic reaction to local anesthesia during pregnancy, unspecified trimester converts to ICD-9-CM 646.80 (preg compl NEC-unspec). The mapping is approximate, so confirm the match fits the documentation.
