2026 ICD-10-CM Diagnosis Code O21Excessive vomiting in pregnancy

ICD-10-CM Codes›O00-O9A›O20-O29›O21

ICD-10-CM O21
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

O21 is a non-billable ICD-10-CM category code for excessive vomiting in pregnancy, so it cannot be submitted on claims. Use a more specific code from this category instead, such as O21.0, O21.1, O21.2, and O21.8.

Code Identity

ICD-10-CM Code
O21
Billable Status
No — Non-Billable Category
Code Describes
Excessive vomiting in pregnancy
Chapter
O20-O29
Other maternal disorders predominantly related to pregnancy

Code Classification

ChapterO00-O9APregnancy, childbirth and the puerperium
SectionO20-O29Other maternal disorders predominantly related to pregnancy
CategoryO21Excessive vomiting in pregnancy
This CodeO21Excessive vomiting in pregnancy

Specific Coding for Excessive vomiting in pregnancyOverview

Non-specific codes like O21 require more characters. Use one of these billable codes instead:

  • Use O21.0 for Mild hyperemesis gravidarum

  • Use O21.1 for Hyperemesis gravidarum with metabolic disturbance

  • Use O21.2 for Late vomiting of pregnancy

  • Use O21.8 for Other vomiting complicating pregnancy

  • Use O21.9 for Vomiting of pregnancy, unspecified

Patient EducationClinical

Health Problems in Pregnancy

A health problem in pregnancy is any disease or condition that could affect your health or the health of your fetus. Some health problems may make it more likely that you will have a high-risk pregnancy. A high-risk pregnancy is one in which you, your fetus, or both are at higher risk for health problems than in a typical pregnancy.

The full article covers:

  • What are health problems in pregnancy?
  • What raises my risk for health problems during pregnancy?
  • Can chronic health conditions cause problems in pregnancy?
  • Can health problems in pregnancy be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About O21Overview

Is O21 (Excessive vomiting in pregnancy) a billable code?

No. This is a category header that groups the codes for excessive vomiting in pregnancy, and headers cannot be submitted on claims. Claims for excessive vomiting in pregnancy need a more specific code from this category, such as O21.0, O21.1, and O21.2.