O41.1291 — Chorioamnionitis, unspecified trimester, fetus 1
Is O41.1291 billable?
Yes, but O41.1291 is an unspecified code. O41.1291 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, O41.1291 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting O41.1291 — the more specific alternatives are listed below.
O41.1291 at a glance
| Code | O41.1291 |
|---|---|
| Description | Chorioamnionitis, unspecified trimester, fetus 1 |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "1" | fetus 1 |
What does the 7th character "1" mean in O41.1291?
In O41.1291, the 7th character 1 means fetus 1. The 7th character is required for O41.1291 to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
Which MS-DRGs does O41.1291 group to?
O41.1291 sits in MDC 14 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 817Other Antepartum Diagnoses with O.R. Procedures with MCCsurgical
- 818Other Antepartum Diagnoses with O.R. Procedures with CCsurgical
- 819Other Antepartum Diagnoses with O.R. Procedures without CC/MCCsurgical
How is O41.1291 listed in the Alphabetic Index?
The Alphabetic Index lists these routes under O41.12, the nearest indexed parent of O41.1291. Use them to find the family, then select the specific code.
- Chorioamnionitis
- Triple I
- Infection, infected, infective › intrauterine inflammation (opportunistic)
- Infection, infected, infective › amniotic fluid, sac or cavity › chorioamnionitis (opportunistic)
- Pregnancy › complicated by › amnionitis (single) (uterine)
- Pregnancy › complicated by › chorioamnionitis (single) (uterine)
- Pregnancy › complicated by › infection › intrauterine (single) (uterine)
- Pregnancy › complicated by › inflammation › intrauterine (single) (uterine)
Excludes1 — never code together — inherited from Chapter 15
The conditions below can never be reported together with O41.1291 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- supervision of normal pregnancy (Z34.-)
Excludes1 — never code together — inherited from O41
The conditions below can never be reported together with O41.1291 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- encounter for suspected maternal and fetal conditions ruled out (Z03.7-)
Use additional code — inherited from Chapter 15
Report an additional code alongside O41.1291 to fully describe the condition. O41.1291 is sequenced first.
- code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.
Excludes2 — not included here — inherited from Chapter 15
The conditions below are not part of O41.1291, but a patient may have both at the same time. When documentation supports it, O41.1291 and the excluded code may both be reported.
How long has O41.1291 existed?
O41.1291 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.