2027 ICD-10-CM Diagnosis Code O40.2XX9Polyhydramnios, second trimester, other fetus
O40.2XX9 is a billable ICD-10-CM diagnosis code for polyhydramnios, second 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 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). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Polyhydramnios and other problems of amniotic cavity.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for O40.2XX9.
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to O40.2XX9: its own notes plus those printed at O40 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.
- encounter for suspected maternal and fetal conditions ruled out (Z03.7-)
- 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.
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
7th Character
Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.
- One of the following 7th characters is to be assigned to each code under category O40. 7th character 0 is for single gestations and multiple gestations where the fetus is unspecified. 7th characters 1 through 9 are for cases of multiple gestations to identify the fetus for which the code applies. The appropriate code from category O30, Multiple gestation, must also be assigned when assigning a code from category O40 that has a 7th character of 1 through 9.
- 0not applicable or unspecified
- 1fetus 1
- 2fetus 2
- 3fetus 3
- 4fetus 4
- 5fetus 5
- 9other fetus this code
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name O40.2XX9, its category, or a range that includes it.
Excludes1 1
These codes carry an Excludes1 note naming O40.2XX9: they are not reported together with it, unless the two conditions are unrelated.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Polyhydramnios
a condition of abnormally high amniotic fluid volume, such as greater than 2,000 ml in the last trimester and usually diagnosed by ultrasonographic criteria (amniotic fluid index). it is associated with maternal diabetes mellitus; multiple pregnancy; chromosomal disorders; and congenital abnormalities.
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.
Convert O40.2XX9 to ICD-9-CMHistory
Code HistoryHistory
Questions About O40.2XX9Overview
What is the ICD-10 code for polyhydramnios, second trimester, other fetus?
The ICD-10-CM code for polyhydramnios, second trimester, other fetus is O40.2XX9 (sometimes written as O402XX9). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is O40.2XX9 (Polyhydramnios, second trimester) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report polyhydramnios, second trimester, other fetus on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What does the 7th character 9 in O40.2XX9 mean?
The final character 9 identifies the fetus in a multiple gestation pregnancy: this code reports polyhydramnios, second trimester for a fetus other than fetus 1 through 5.
What MS-DRG does O40.2XX9 group to?
When polyhydramnios, second trimester, other fetus 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 O40.2XX9 be reported for?
The Medicare Code Editor checks polyhydramnios, second 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.
