O21.1 – Hyperemesis gravidarum with metabolic disturbance

ICD-10-CM 2027 diagnosis code · Other maternal disorders predominantly related to pregnancy

Billable code

ICD-10-CM code O21.1

Code: O21.1 (claims format: O211)
Description: Hyperemesis gravidarum with metabolic disturbance
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 15. Pregnancy, childbirth and the puerperium (O00-O9A)
Block: O20-O29 Other maternal disorders predominantly related to pregnancy
Parent codes: O21

Notes for O21.1

Applicable to:

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

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

Block O20-O29

Excludes2 (not included here):

maternal care related to the fetus and amniotic cavity and possible delivery problems (O30-O48)
maternal diseases classifiable elsewhere but complicating pregnancy, labor and delivery, and the puerperium (O98-O99)

Index terms for O21.1

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in O21

O21.0 – Mild hyperemesis gravidarumBillable
O21.2 – Late vomiting of pregnancyBillable
O21.8 – Other vomiting complicating pregnancyBillable
O21.9 – Vomiting of pregnancy, unspecifiedBillable

Frequently asked questions

What is ICD-10 code O21.1?

O21.1 is the ICD-10-CM code for hyperemesis gravidarum with metabolic disturbance, in the block O20-O29 (Other maternal disorders predominantly related to pregnancy).

Is O21.1 a billable code?

Yes. O21.1 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does O21.1 belong to?

It belongs to category O21 – Excessive vomiting in pregnancy.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.