2024 ICD-10-CM Diagnosis Code O21.9

Vomiting of pregnancy, unspecified

ICD-10-CM Code:
O21.9
ICD-10 Code for:
Vomiting of pregnancy, unspecified
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Not chronic
Code Navigator:

Code Classification

  • Pregnancy, childbirth and the puerperium
    (O00-O9A)
    • Other maternal disorders predominantly related to pregnancy
      (O20-O29)
      • Excessive vomiting in pregnancy
        (O21)

O21.9 is a billable diagnosis code used to specify a medical diagnosis of vomiting of pregnancy, unspecified. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

The code O21.9 is applicable to female patients aged 12 through 55 years inclusive. It is clinically and virtually impossible to use this code on a non-female patient outside the stated age range.

The code is commonly used in ob/gyn medical specialties to specify clinical concepts such as maternal disorders related to pregnancy.

Unspecified diagnosis codes like O21.9 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Hypertension AND/OR vomiting complicating pregnancy childbirth AND/OR puerperium
  • Morning sickness
  • Vomiting of pregnancy

Clinical Classification

Clinical CategoryCCSR Category CodeInpatient Default CCSROutpatient Default CCSR
Nausea and vomitingSYM004N - Not default inpatient assignment for principal diagnosis or first-listed diagnosis.N - Not default outpatient assignment for principal diagnosis or first-listed diagnosis.
Other specified complications in pregnancyPRG028Y - Yes, default inpatient assignment for principal diagnosis or first-listed diagnosis.Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.

Clinical Information

  • Morning Sickness

    symptoms of nausea and vomiting in pregnant women that usually occur in the morning during the first 2 to 3 months of pregnancy. severe persistent vomiting during pregnancy is called hyperemesis gravidarum.
  • Morning Sickness

    the nausea and vomiting that accompanies early pregnancy.

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10-CM Code Edits are applicable to this code:

  • Maternity diagnoses - The Medicare Code Editor detects inconsistencies in maternity cases by checking a patient's age and any diagnosis on the patient's record. The maternity code edits apply to patients age ange is 9–64 years inclusive (e.g., diabetes in pregnancy, antepartum pulmonary complication).
  • Diagnoses for females only - The Medicare Code Editor detects inconsistencies between a patient’s sex and any diagnosis on the patient’s record, these edits apply to FEMALES only .

Convert O21.9 to ICD-9-CM

  • ICD-9-CM Code: 643.93 - Vomit of pg NOS-antepart
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

Patient Education


Nausea and Vomiting

What are nausea and vomiting?

Nausea is when you feel sick to your stomach, as if you are going to throw up. Vomiting is when you throw up.

What causes nausea and vomiting?

Nausea and vomiting can be symptoms of many different conditions, including:

  • Morning sickness during pregnancy
  • Gastroenteritis (infection of your intestines) and other infections
  • Migraines
  • Motion sickness
  • Food poisoning
  • Medicines, including those for cancer chemotherapy
  • GERD (reflux) and ulcers
  • Intestinal obstruction

When do I need to see a health care provider for nausea and vomiting?

Nausea and vomiting are common. They are usually not serious. However, you should contact your health care provider immediately if you have:

  • A reason to think that your vomiting is from poisoning
  • Vomited for longer than 24 hours
  • Blood in the vomit
  • Severe abdominal pain
  • Severe headache and stiff neck
  • Signs of dehydration, such as dry mouth, infrequent urination or dark urine

How is the cause of nausea and vomiting diagnosed?

Your health care provider will take your medical history, ask about your symptoms and do a physical exam. The provider will look for signs of dehydration. You may have some tests, including blood and urine tests. Women may also have a pregnancy test.

What are the treatments for nausea and vomiting?

Treatments for nausea and vomiting depend on the cause. You may get treatment for the underlying problem. There are some medicines that can treatment nausea and vomiting. For severe cases of vomiting, you may need extra fluids through an IV (intravenous).

There are things that you can do to feel better:

  • Get enough fluids, to avoid dehydration. If you are having trouble keeping liquids down, drink small amounts of clear liquids often.
  • Eat bland foods; stay away from spicy, fatty, or salty foods
  • Eat smaller meals more often
  • Avoid strong smells, since they can sometimes trigger nausea and vomiting
  • If you are pregnant and have morning sickness, eat crackers before you get out of bed in the morning

[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.