O00.521 — Right cornual ectopic pregnancy with intrauterine pregnancy
Is O00.521 billable?
Yes — O00.521 is billable for FY2027. O00.521 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. O00.521 may be submitted for encounters from October 1, 2026 through September 30, 2027. O00.521 is new in FY2027.
O00.521 at a glance
| Code | O00.521 |
|---|---|
| Description | Right cornual ectopic pregnancy with intrauterine pregnancy |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| FY2027 change | New in FY2027 |
Which MS-DRGs does O00.521 group to?
O00.521 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
As a secondary diagnosis, O00.521 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is O00.521 listed in the Alphabetic Index?
The Alphabetic Index lists these routes under O00.52, the nearest indexed parent of O00.521. Use them to find the family, then select the specific code.
- Cornual gestation or pregnancy › with intrauterine pregnancy
- Pregnancy › cornual › with intrauterine pregnancy (single) (uterine)
- Pregnancy › ectopic › cornual › with intrauterine pregnancy (single) (uterine)
Excludes1 — never code together — inherited from Chapter 15
The conditions below can never be reported together with O00.521 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 O00-O08
The conditions below can never be reported together with O00.521 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Use additional code — inherited from Chapter 15
Report an additional code alongside O00.521 to fully describe the condition. O00.521 is sequenced first.
- code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.
Use additional code — inherited from O00
Report an additional code alongside O00.521 to fully describe the condition. O00.521 is sequenced first.
- code from category O08 to identify any associated complication
Excludes2 — not included here — inherited from Chapter 15
The conditions below are not part of O00.521, but a patient may have both at the same time. When documentation supports it, O00.521 and the excluded code may both be reported.