O21.1 — Hyperemesis gravidarum with metabolic disturbance
O21.1 is a billable, specific ICD-10-CM code for hyperemesis gravidarum with metabolic disturbance. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Hyperemesis gravidarum, starting before the end of the 20th week of gestation, with metabolic disturbance such as carbohydrate depletion
- Hyperemesis gravidarum, starting before the end of the 20th week of gestation, with metabolic disturbance such as dehydration
- Hyperemesis gravidarum, starting before the end of the 20th week of gestation, with metabolic disturbance such as electrolyte imbalance
Other codes that can never be billed with O21.1
These codes carry an Excludes1 note pointing at O21.1. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading O21.1 alone.
- E87Other disorders of fluid, electrolyte and acid-base balance
Risk adjustment
O21.1 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
O21.1 is named in 1 Medicare coverage policy — 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A57189Billing and Coding: Serum Magnesium
How O21.1 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to O21.1.
- Hyperemesis›gravidarum›severe(with metabolic disturbance)
- Imbalance›electrolyte›due to hyperemesis gravidarum
- Hyperemesis›gravidarum›with›carbohydrate depletion
- Hyperemesis›gravidarum›with›dehydration
- Hyperemesis›gravidarum›with›electrolyte imbalance
- Hyperemesis›gravidarum›with›metabolic disturbance
Related codes at this level
Codes that share O21. If O21.1 is not quite right, the correct code is usually one of these.
Questions about O21.1
- Is O21.1 a billable ICD-10-CM code?
- Yes. O21.1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does O21.1 sit in the tabular list?
- Pregnancy, childbirth and the puerperium (O00-O9A), in the block Other maternal disorders predominantly related to pregnancy (O20-O29).