O40.9 – Polyhydramnios, unspecified trimester
ICD-10-CM 2027 diagnosis code · Maternal care related to the fetus and amniotic cavity and possible delivery problems
- Code
O40.9(claims format:O409)- Description
- Polyhydramnios, unspecified trimester
- Billable
- No – use a more specific code below
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 15. Pregnancy, childbirth and the puerperium (O00-O9A)
- Block
- O30-O48 Maternal care related to the fetus and amniotic cavity and possible delivery problems
- Parent codes
- O40
Billable codes under O40.9
O40.9 is a header code and cannot be used on claims. Choose the most specific code:
- O40.9XX0 – Polyhydramnios, unspecified trimester, not applicable or unspecifiedBillable
- O40.9XX1 – Polyhydramnios, unspecified trimester, fetus 1Billable
- O40.9XX2 – Polyhydramnios, unspecified trimester, fetus 2Billable
- O40.9XX3 – Polyhydramnios, unspecified trimester, fetus 3Billable
- O40.9XX4 – Polyhydramnios, unspecified trimester, fetus 4Billable
- O40.9XX5 – Polyhydramnios, unspecified trimester, fetus 5Billable
- O40.9XX9 – Polyhydramnios, unspecified trimester, other fetusBillable
7th character values
Codes in this category need a 7th character to describe the encounter or episode of care (use placeholder X for empty positions).
| Character | Meaning |
|---|---|
0 | not applicable or unspecified |
1 | fetus 1 |
2 | fetus 2 |
3 | fetus 3 |
4 | fetus 4 |
5 | fetus 5 |
9 | other fetus |
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
O40 – Polyhydramnios
- hydramnios
- encounter for suspected maternal and fetal conditions ruled out (Z03.7-)
- 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.
Related codes in O40
Frequently asked questions
What is ICD-10 code O40.9?
O40.9 is the ICD-10-CM code for polyhydramnios, unspecified trimester, in the block O30-O48 (Maternal care related to the fetus and amniotic cavity and possible delivery problems).
Is O40.9 a billable code?
No. O40.9 is a header code with more specific child codes; report one of the billable codes listed above.
What category does O40.9 belong to?
It belongs to category O40 – Polyhydramnios.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.