O36 vs O36.2
O36 and O36.2 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 O36.2
hydrops fetalis associated with ABO isoimmunization (O36.1-)
O36
Maternal care for other fetal problems
Not billable
- Chapter 15
- Pregnancy, childbirth and the puerperium
- Section
- O30-O48
Use when the record says
- the listed conditions in the fetus as a reason for hospitalization or other obstetric care of the mother, or for termination of pregnancy
O36.2
Maternal care for hydrops fetalis
Not billable
- Chapter 15
- Pregnancy, childbirth and the puerperium
- Section
- O30-O48
Use when the record says
- Maternal care for hydrops fetalis NOS
- Maternal care for hydrops fetalis not associated with isoimmunization
Indexed under
- Pregnancy › complicated by › hydrops › fetalis (single) (uterine)
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