O75.2 vs R50
O75.2 and R50 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on R50
fever of unknown origin during labor (O75.2)
O75.2
Pyrexia during labor, not elsewhere classified
BillableUnspecified
- Chapter 15
- Pregnancy, childbirth and the puerperium
- Section
- O60-O77
Indexed under
- Pyrexia › during labor NEC (of unknown origin)
- Delivery › complicated › by › fever during labor (childbirth) (labor)
R50
Fever of other and unknown origin
Not billable
- Chapter 18
- Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
- Section
- R50-R69
These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027