2026 ICD-10-CM Diagnosis Code O42.90Premature rupture of membranes, unspecified as to length of time between rupture and onset of labor, unspecified weeks of gestation

ICD-10-CM Codes›O00-O9A›O30-O48›O42

ICD-10-CM O42.90
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

O42.90 is a billable ICD-10-CM diagnosis code for premature rupture of membranes, unspecified as to length of time between rupture and onset of labor, unspecified weeks of gestation. 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 Early or threatened labor.

Code Identity

ICD-10-CM Code
O42.90
Billable Status
Yes — Valid for Submission
Code Describes
Premature rupture of membranes, unspecified as to length of time between rupture and onset of labor, unspecified weeks of gestation
Short Description
Prem ROM, 7th0 betw rupt & onst labr, unsp weeks of gest
Parent Code
O42.9
Premature rupture of membranes, unspecified as to length of time between rupture and onset of labor

Code Classification

ChapterO00-O9APregnancy, childbirth and the puerperium
SectionO30-O48Maternal care related to the fetus and amniotic cavity and possible delivery problems
CategoryO42Premature rupture of membranes
This CodeO42.90Premature rupture of membranes, unspecified as to length of time between rupture and onset of labor, unspecified weeks of gestation

Code EditsBilling

Medicare Code Editor checks that affect claim validity for O42.90.

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.

  • Amniotic fluid leaking
  • Fetal disorder due to disorder of amniotic cavity and/or membrane
  • Fetal disorder due to premature rupture of membranes
  • Finding related to amniotic fluid production
  • Hydrorrhea gravidarum
  • Oligohydramnios
  • Oligohydramnios due to rupture of membranes
  • Premature rupture of membranes
  • Premature rupture of membranes, labor delayed by therapy
  • Prolonged premature rupture of membranes
  • Prolonged rupture of membranes
  • Prolonged spontaneous rupture of membranes
  • Rupture of amniotic membrane detected by nitrazine yellow test
  • Spontaneous rupture of fetal membranes

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.

    • Delivery(childbirth) (labor)
      • complicated
        • by
          • premature rupture, membranes
    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • hydrorrhea
    • Pregnancy(single) (uterine)
      • complicated by (care of) (management affected by)
        • premature rupture of membranes

Clinical ClassificationClinical

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

CCSR PRG011
Early or threatened labor
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Oligohydramnios

    a condition of abnormally low amniotic fluid volume. principal causes include malformations of fetal urinary tract; fetal growth retardation; gestational hypertension; nicotine poisoning; and prolonged pregnancy.

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 O42.90 to ICD-9-CMHistory

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

ICD-9-CM
658.10 Prem rupt membran-unspec
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 O42.90Overview

Is O42.90 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report premature rupture of membranes, unspecified as to length of time between rupture and onset of labor, unspecified weeks of gestation on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does O42.90 group to?

When premature rupture of membranes, unspecified as to length of time between rupture and onset of labor, unspecified weeks of gestation 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 O42.90 be reported for?

The Medicare Code Editor checks premature rupture of membranes, unspecified as to length of time between rupture and onset of labor, unspecified weeks of gestation 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 O42.90?

Under the General Equivalence Mappings, premature rupture of membranes, unspecified as to length of time between rupture and onset of labor, unspecified weeks of gestation converts to ICD-9-CM 658.10 (prem rupt membran-unspec). 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.