O16: Unspecified maternal hypertension
Codes under O16 (Unspecified maternal hypertension). A ✓ marks a billable (fully specified) code; category codes without a ✓ are not billable on their own.
| Code | Description | Billable |
|---|---|---|
| O16.1 | Unspecified maternal hypertension, first trimester | ✓ |
| O16.1 | Unspecified maternal hypertension, first trimester | ✓ |
| O16.2 | Unspecified maternal hypertension, second trimester | ✓ |
| O16.2 | Unspecified maternal hypertension, second trimester | ✓ |
| O16.3 | Unspecified maternal hypertension, third trimester | ✓ |
| O16.3 | Unspecified maternal hypertension, third trimester | ✓ |
| O16.4 | Unspecified maternal hypertension, complicating childbirth | ✓ |
| O16.4 | Unspecified maternal hypertension, complicating childbirth | ✓ |
| O16.5 | Unspecified maternal hypertension, complicating the puerperium | ✓ |
| O16.5 | Unspecified maternal hypertension, complicating the puerperium | ✓ |
| O16.9 | Unspecified maternal hypertension, unspecified trimester | ✓ |
| O16.9 | Unspecified maternal hypertension, unspecified trimester | ✓ |
Frequently asked questions
What is ICD-10-CM code O16?
O16 is an ICD-10-CM category covering Unspecified maternal hypertension. It contains 12 more specific diagnosis codes, 12 of which are billable.
Is O16 a billable code?
No — O16 is a category header and isn't billable on its own. Code to the highest level of specificity using one of its subcodes (for example O16.1 — Unspecified maternal hypertension, first trimester). 12 of the 12 codes under O16 are billable.
What codes fall under O16?
O16 includes O16.1, O16.1, O16.2, O16.2, O16.3, plus 7 more. See the full list with descriptions and billable status above.
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Informational only, not coding or medical advice. Verify against the official ICD-10-CM (FY2026) and your payer's guidelines.
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