2026 ICD-10-CM Diagnosis Code O99.891Other specified diseases and conditions complicating pregnancy

ICD-10-CM Codes›O00-O9A›O94-O9A›O99

ICD-10-CM O99.891
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

O99.891 is a billable ICD-10-CM diagnosis code for other specified diseases and conditions complicating 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 Other specified complications in pregnancy.

Code Identity

ICD-10-CM Code
O99.891
Billable Status
Yes — Valid for Submission
Code Describes
Other specified diseases and conditions complicating pregnancy
Short Description
Oth diseases and conditions complicating pregnancy
Parent Code
O99.89
Other specified diseases and conditions complicating pregnancy, childbirth and the puerperium

Code Classification

ChapterO00-O9APregnancy, childbirth and the puerperium
SectionO94-O9AOther obstetric conditions, not elsewhere classified
CategoryO99Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium
This CodeO99.891Other specified diseases and conditions complicating pregnancy

Code EditsBilling

Medicare Code Editor checks that affect claim validity for O99.891.

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).

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abscess of nipple
  • Bicornuate uterus
  • Bicornuate uterus in pregnancy, childbirth and the puerperium
  • Bleeding from nose
  • Bone AND/OR joint disorder in mother complicating pregnancy, childbirth AND/OR puerperium
  • Bone AND/OR joint disorder of back in mother complicating pregnancy, childbirth AND/OR puerperium
  • Bone AND/OR joint disorder of lower extremities in mother complicating pregnancy, childbirth AND/OR puerperium
  • Bone AND/OR joint disorder of pelvis in mother complicating pregnancy, childbirth AND/OR puerperium
  • Congenital abnormal shape of fallopian tube
  • Congenital abnormality of uterus in pregnancy, childbirth and the puerperium
  • Congenital anomaly of mother complicating pregnancy
  • Congenital cardiovascular disorder in mother complicating pregnancy, childbirth AND/OR puerperium
  • Congenital cardiovascular disorders during pregnancy, childbirth and the puerperium
  • Congenital heart disease in pregnancy
  • Cystocele in pregnancy, childbirth and the puerperium
  • Disease of nervous system complicating pregnancy, childbirth and puerperium
  • Disease of skin and subcutaneous tissue complicating pregnancy, childbirth and/or puerperium
  • Disease of the respiratory system complicating pregnancy, childbirth and/or the puerperium
  • Fat embolism - obstetric
  • Fetal disorder due to maternal autoimmune disease
  • Fetal disorder due to maternal disorder of urinary tract
  • Fetal disorder due to maternal renal disease
  • Fetal disorder due to previous maternal pelvic surgery
  • Fetal disorder due to previous maternal uterine surgery
  • Finding of tone of female perineum
  • Heart disease in mother complicating pregnancy, childbirth AND/OR puerperium
  • Hypertensive heart disease in obstetric context
  • Hypertensive renal disease in obstetric context
  • Idiopathic osteoporosis
  • Idiopathic osteoporosis in pregnancy
  • Maternal perinatal disorder
  • Maternal perinatal epistaxis
  • Maternal perinatal jaundice
  • Maternal perinatal sensorineural hearing loss
  • Musculoskeletal problem in pregnancy
  • Neoplasm of body of uterus in pregnancy, childbirth and puerperium
  • Obstetric abscess of breast
  • Obstetric abscess of nipple
  • Obstetric anesthesia problems
  • Obstetric disorder of uterus
  • Obstetric infection of breast
  • Obstetric mastitis
  • Obstetric pulmonary embolism
  • Obstetric pulmonary thromboembolism
  • Obstetric pyemic and septic pulmonary embolism
  • Obstetrical blood clot embolism
  • Obstetrical pulmonary fat embolism
  • Orthopedic disorders during pregnancy, childbirth and the puerperium
  • Pelvic mass in pregnancy
  • Pelvic soft tissue abnormality in pregnancy, childbirth and the puerperium
  • Perinatal depression
  • Polyp of cervix in pregnancy, childbirth and the puerperium
  • Prediabetes
  • Prediabetes in mother during pregnancy
  • Pre-existing maternal disease complicating pregnancy
  • Pregnancy with orthopedic problem
  • Pulmonary fat embolism
  • Pulmonary thromboembolism
  • Pulmonary thrombosis
  • Rigid perineum
  • Rigid perineum in pregnancy, childbirth, and/or puerperium
  • Rubella in mother complicating pregnancy, childbirth AND/OR puerperium
  • Septic embolus of artery
  • Septic pulmonary embolism
  • Transient osteoporosis
  • Transient osteoporosis of hip
  • Transient osteoporosis of hip in pregnancy
  • Uterine fibroids in pregnancy, childbirth and the puerperium

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • connective system disorders (conditions in M00-M99)
    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • diseases of
          • specified NEC
    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • disorders of
          • ear and mastoid process (conditions in H60-H95)
    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • disorders of
          • eye and adnexa (conditions in H00-H59)
    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • disorders of
          • specified NEC
    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • musculoskeletal condition (conditions is M00-M99)
    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • pelvic inflammatory disease
    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • peritoneal (pelvic) adhesions

Clinical ClassificationClinical

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

CCSR PRG028
Other specified complications in pregnancy
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Bicornuate Uterus

    a congenital uterine anomaly in which the uterus is divided into two uterine horns with a significant cleft at the uterine fundus due to partial fusion of the mullerian ducts. bicornuate uterus is sometimes associated with a longitudinal vaginal septum and abnormal development of renal tracts.

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.

Code History & ChangesHistory

Replacement O99.891 replaces the following previously assigned code(s):

  • O99.89 - Oth diseases and conditions compl preg/chldbrth
FY 2021AddedAdded to the ICD-10-CM code setEffective October 1, 2020.
FY 2022–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About O99.891Overview

Is O99.891 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other specified diseases and conditions complicating pregnancy on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does O99.891 group to?

When other specified diseases and conditions complicating pregnancy 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 O99.891 be reported for?

The Medicare Code Editor checks other specified diseases and conditions complicating pregnancy against patient demographics: this code is intended for maternity cases (age 9 through 64). Claims outside these limits are flagged as inconsistent.

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.