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v1.0.0
ICD-10 Guide
ICD-10 CodesO21.0

O21.0

Billable

Mild hyperemesis gravidarum

BILLABLE STATUSYes
IMPLEMENTATION DATEOctober 1, 2015
LAST UPDATED09/08/2025

Code Description

ICD-10 O21.0 is a billable code used to indicate a diagnosis of mild hyperemesis gravidarum.

Key Diagnostic Point:

Mild hyperemesis gravidarum is characterized by persistent nausea and vomiting during pregnancy that is severe enough to cause dehydration and nutritional deficiencies but does not require hospitalization. It typically occurs in the first trimester and can lead to weight loss and electrolyte imbalances. Patients may experience symptoms such as excessive vomiting, inability to keep food down, and fatigue. Management often includes dietary modifications, hydration, and sometimes pharmacological interventions to alleviate symptoms. While mild hyperemesis gravidarum is less severe than its counterpart, severe hyperemesis gravidarum, it still requires careful monitoring to prevent complications for both the mother and fetus. Nutritional support is crucial, and healthcare providers may recommend small, frequent meals, hydration with electrolyte solutions, and, in some cases, vitamin supplementation to ensure adequate nutrition during this challenging period.

Code Complexity Analysis

Complexity Rating: Medium

Medium Complexity

Complexity Factors

  • Differentiating between mild and severe hyperemesis gravidarum
  • Understanding the impact of dehydration on pregnancy outcomes
  • Navigating nutritional support documentation requirements
  • Recognizing associated conditions that may complicate coding

Audit Risk Factors

  • Inadequate documentation of symptom severity
  • Failure to document nutritional interventions
  • Misclassification of hyperemesis severity
  • Lack of follow-up notes on patient progress

Specialty Focus

Medical Specialties

Obstetrics and Gynecology

Documentation Requirements

Documentation should include detailed accounts of symptoms, treatment plans, and any nutritional support provided.

Common Clinical Scenarios

Patients presenting with persistent nausea and vomiting, requiring outpatient management and dietary counseling.

Billing Considerations

Coders must ensure that the documentation clearly indicates the severity of symptoms to differentiate between mild and severe cases.

Maternal-Fetal Medicine

Documentation Requirements

High-risk pregnancy documentation should include comprehensive assessments of maternal and fetal health, including hydration status and nutritional intake.

Common Clinical Scenarios

Complex cases involving patients with pre-existing conditions exacerbated by hyperemesis gravidarum.

Billing Considerations

Considerations for high-risk coding include monitoring for potential complications such as electrolyte imbalances and fetal growth restrictions.

Coding Guidelines

Inclusion Criteria

Use O21.0 When
  • Coders should follow the official ICD
  • CM guidelines for obstetric coding, ensuring that the diagnosis is supported by clinical documentation and that any associated conditions are accurately captured

Exclusion Criteria

Do NOT use O21.0 When
No specific exclusions found.

Related ICD-10 Codes

Related CPT Codes

99213CPT Code

Established patient office visit, Level 3

Clinical Scenario

Used for follow-up visits for patients with mild hyperemesis gravidarum.

Documentation Requirements

Document the patient's symptoms, treatment plan, and any changes in condition.

Specialty Considerations

Obstetricians should ensure that the visit notes reflect the ongoing management of hyperemesis.

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The transition to ICD-10 has allowed for more specific coding of conditions like hyperemesis gravidarum, improving the accuracy of diagnosis and treatment tracking.

ICD-9 vs ICD-10

The transition to ICD-10 has allowed for more specific coding of conditions like hyperemesis gravidarum, improving the accuracy of diagnosis and treatment tracking.

Reimbursement & Billing Impact

The transition to ICD-10 has allowed for more specific coding of conditions like hyperemesis gravidarum, improving the accuracy of diagnosis and treatment tracking.

Resources

Clinical References

  • •
    American College of Obstetricians and Gynecologists (ACOG) Guidelines

Coding & Billing References

  • •
    American College of Obstetricians and Gynecologists (ACOG) Guidelines

Frequently Asked Questions

What is the difference between mild and severe hyperemesis gravidarum?

Mild hyperemesis gravidarum involves persistent nausea and vomiting without the need for hospitalization, while severe hyperemesis gravidarum requires hospitalization due to significant dehydration and nutritional deficiencies.