2026 ICD-10-CM Diagnosis Code O31.13X9Continuing pregnancy after spontaneous abortion of one fetus or more, third trimester, other fetus

ICD-10-CM Codes›O00-O9A›O30-O48›O31

ICD-10-CM O31.13X9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

O31.13X9 is a billable ICD-10-CM diagnosis code for continuing pregnancy after spontaneous abortion of one fetus or more, third trimester, other fetus. The 7th character 9 identifies a fetus other than fetus 1 through 5 in a multiple gestation pregnancy. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) 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). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Multiple gestation.

Code Identity

ICD-10-CM Code
O31.13X9
Billable Status
Yes — Valid for Submission
Code Describes
Continuing pregnancy after spontaneous abortion of one fetus or more, third trimester, other fetus
Short Description
Cont preg aft spon abort of one fts or more, third tri, oth
Parent Code
O31.13
Continuing pregnancy after spontaneous abortion of one fetus or more, third trimester

Code Classification

ChapterO00-O9APregnancy, childbirth and the puerperium
SectionO30-O48Maternal care related to the fetus and amniotic cavity and possible delivery problems
CategoryO31Complications specific to multiple gestation
This CodeO31.13X9Continuing pregnancy after spontaneous abortion of one fetus or more, third trimester, other fetus

Code EditsBilling

Medicare Code Editor checks that affect claim validity for O31.13X9.

Maternity diagnoses
The Medicare Code Editor detects inconsistencies in maternity cases by checking a patient's age and any diagnosis on the patient's record. The maternity code edits apply to patients age ange is 9–64 years inclusive (e.g., diabetes in pregnancy, antepartum pulmonary complication).

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR PRG012
Multiple gestation
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Miscarriage

A miscarriage is an unexpected loss of pregnancy before the 20th week. Most miscarriages happen very early in the pregnancy, often before a woman even knows she is pregnant.

The full article covers:

  • What is a miscarriage?
  • What causes a miscarriage?
  • What are the signs of a miscarriage?
  • How is a miscarriage diagnosed?
  • What is the treatment for a miscarriage?
  • Can a miscarriage be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert O31.13X9 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
651.61 Mult ges w fet loss-del
Approximate The match is approximate rather than exact.
ICD-9-CM
651.63 Mult ges w fet loss-ante
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About O31.13X9Overview

Is O31.13X9 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report continuing pregnancy after spontaneous abortion of one fetus or more, third trimester, other fetus on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character 9 in O31.13X9 mean?

The final character 9 identifies the fetus in a multiple gestation pregnancy: this code reports continuing pregnancy after spontaneous abortion of one fetus or more, third trimester for a fetus other than fetus 1 through 5.

What MS-DRG does O31.13X9 group to?

When continuing pregnancy after spontaneous abortion of one fetus or more, third trimester, other fetus is the principal diagnosis on an inpatient stay, it groups to MS-DRG 817, 818, 819, 831, 832, 833, with relative weights from 0.5229 to 1.6880 depending on complications. Higher weights mean higher Medicare reimbursement.

Who can O31.13X9 be reported for?

The Medicare Code Editor checks continuing pregnancy after spontaneous abortion of one fetus or more, third trimester, other fetus 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 O31.13X9?

Under the General Equivalence Mappings, continuing pregnancy after spontaneous abortion of one fetus or more, third trimester, other fetus converts to ICD-9-CM 651.61 (mult ges w fet loss-del) and 651.63 (mult ges w fet loss-ante). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.