Excessive vomiting in pregnancy (O21) ICD-10-CM
The O21 code range covers excessive vomiting in pregnancy with 6 ICD-10-CM diagnosis codes. 5 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Codes in the O21 Range 6 codes · 5 billable
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the O21 range.
Hyperemesis Gravidarum
Intractable VOMITING that develops in early PREGNANCY and persists. This can lead to DEHYDRATION and WEIGHT LOSS.
Morning Sickness
Symptoms of NAUSEA and VOMITING in PREGNANT PEOPLE that usually occur in the morning during the first 2 to 3 months of PREGNANCY. Severe persistent vomiting during pregnancy is called HYPEREMESIS GRAVIDARUM.
About the O21 Code Range
The ICD-10 code section O21 covers excessive vomiting during pregnancy, capturing various severities and related complications. These codes are used for diagnosing and documenting conditions ranging from mild to severe vomiting that impacts pregnancy health.
This section includes O21.0, representing mild or moderate hyperemesis gravidarum, a condition also known simply as "hyperemesis" or "moderate hyperemesis gravidarum." More severe cases involving metabolic imbalances like dehydration or electrolyte disturbances are classified under O21.1, which specifies hyperemesis gravidarum with metabolic disturbance occurring before 22 weeks gestation. Vomiting that happens later in pregnancy, such as during the third trimester, falls under O21.2, commonly referred to as "late vomiting of pregnancy." The code O21.8 covers other vomiting causes related to organic diseases complicating pregnancy. Finally, O21.9 is used when vomiting of pregnancy is not further specified and includes related terms like nausea, morning sickness, or vomiting that complicates pregnancy and childbirth. These distinctions help healthcare providers accurately code and manage excessive vomiting in pregnancy depending on timing, severity, and underlying issues.
Questions About This Page
How many billable codes are in the O21 range?
Of the 6 codes in this range, 5 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the O21 range classify?
The range classifies excessive vomiting in pregnancy. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
