ICD-10 · PDGM grouping
O21 Excessive vomiting in pregnancy
All 5 codes in the O21 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
5
Can lead a claim
5
Cannot lead a claim
0
What CMS assigns to O21
All 5 codes group to MMTA - Other. None of the 5 is assigned a comorbidity subgroup. Every code can lead a claim.
Every code in O21
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| O21.0 | Mild hyperemesis gravidarum | Can lead a claim | A | None |
| O21.1 | Hyperemesis gravidarum with metabolic disturbance | Can lead a claim | A | None |
| O21.2 | Late vomiting of pregnancy | Can lead a claim | A | None |
| O21.8 | Other vomiting complicating pregnancy | Can lead a claim | A | None |
| O21.9 | Vomiting of pregnancy, unspecified | Can lead a claim | A | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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