ICD-10-CM category
Z3A: Weeks of gestation
Codes under Z3A (Weeks of gestation). A ✓ marks a billable (fully specified) code; category codes without a ✓ are not billable on their own.
| Code | Description | Billable |
|---|---|---|
| Z3A.0 | Weeks of gestation of pregnancy, unspecified or less than 10 weeks | — |
| Z3A.0 | Weeks of gestation of pregnancy, unspecified or less than 10 weeks | — |
| Z3A.00 | Weeks of gestation of pregnancy not specified | ✓ |
| Z3A.00 | Weeks of gestation of pregnancy not specified | ✓ |
| Z3A.01 | Less than 8 weeks gestation of pregnancy | ✓ |
| Z3A.01 | Less than 8 weeks gestation of pregnancy | ✓ |
| Z3A.1 | Weeks of gestation of pregnancy, weeks 10-19 | — |
| Z3A.1 | Weeks of gestation of pregnancy, weeks 10-19 | — |
| Z3A.2 | Weeks of gestation of pregnancy, weeks 20-29 | — |
| Z3A.2 | Weeks of gestation of pregnancy, weeks 20-29 | — |
| Z3A.3 | Weeks of gestation of pregnancy, weeks 30-39 | — |
| Z3A.3 | Weeks of gestation of pregnancy, weeks 30-39 | — |
| Z3A.4 | Weeks of gestation of pregnancy, weeks 40 or greater | — |
| Z3A.4 | Weeks of gestation of pregnancy, weeks 40 or greater | — |
| Z3A.08 | 8 weeks gestation of pregnancy | ✓ |
| Z3A.08 | 8 weeks gestation of pregnancy | ✓ |
| Z3A.09 | 9 weeks gestation of pregnancy | ✓ |
| Z3A.09 | 9 weeks gestation of pregnancy | ✓ |
| Z3A.10 | 10 weeks gestation of pregnancy | ✓ |
| Z3A.10 | 10 weeks gestation of pregnancy | ✓ |
| Z3A.11 | 11 weeks gestation of pregnancy | ✓ |
| Z3A.11 | 11 weeks gestation of pregnancy | ✓ |
| Z3A.12 | 12 weeks gestation of pregnancy | ✓ |
| Z3A.12 | 12 weeks gestation of pregnancy | ✓ |
| Z3A.13 | 13 weeks gestation of pregnancy | ✓ |
| Z3A.13 | 13 weeks gestation of pregnancy | ✓ |
| Z3A.14 | 14 weeks gestation of pregnancy | ✓ |
| Z3A.14 | 14 weeks gestation of pregnancy | ✓ |
| Z3A.15 | 15 weeks gestation of pregnancy | ✓ |
| Z3A.15 | 15 weeks gestation of pregnancy | ✓ |
| Z3A.16 | 16 weeks gestation of pregnancy | ✓ |
| Z3A.16 | 16 weeks gestation of pregnancy | ✓ |
| Z3A.17 | 17 weeks gestation of pregnancy | ✓ |
| Z3A.17 | 17 weeks gestation of pregnancy | ✓ |
| Z3A.18 | 18 weeks gestation of pregnancy | ✓ |
| Z3A.18 | 18 weeks gestation of pregnancy | ✓ |
| Z3A.19 | 19 weeks gestation of pregnancy | ✓ |
| Z3A.19 | 19 weeks gestation of pregnancy | ✓ |
| Z3A.20 | 20 weeks gestation of pregnancy | ✓ |
| Z3A.20 | 20 weeks gestation of pregnancy | ✓ |
| Z3A.21 | 21 weeks gestation of pregnancy | ✓ |
| Z3A.21 | 21 weeks gestation of pregnancy | ✓ |
| Z3A.22 | 22 weeks gestation of pregnancy | ✓ |
| Z3A.22 | 22 weeks gestation of pregnancy | ✓ |
| Z3A.23 | 23 weeks gestation of pregnancy | ✓ |
| Z3A.23 | 23 weeks gestation of pregnancy | ✓ |
| Z3A.24 | 24 weeks gestation of pregnancy | ✓ |
| Z3A.24 | 24 weeks gestation of pregnancy | ✓ |
| Z3A.25 | 25 weeks gestation of pregnancy | ✓ |
| Z3A.25 | 25 weeks gestation of pregnancy | ✓ |
| Z3A.26 | 26 weeks gestation of pregnancy | ✓ |
| Z3A.26 | 26 weeks gestation of pregnancy | ✓ |
| Z3A.27 | 27 weeks gestation of pregnancy | ✓ |
| Z3A.27 | 27 weeks gestation of pregnancy | ✓ |
| Z3A.28 | 28 weeks gestation of pregnancy | ✓ |
| Z3A.28 | 28 weeks gestation of pregnancy | ✓ |
| Z3A.29 | 29 weeks gestation of pregnancy | ✓ |
| Z3A.29 | 29 weeks gestation of pregnancy | ✓ |
| Z3A.30 | 30 weeks gestation of pregnancy | ✓ |
| Z3A.30 | 30 weeks gestation of pregnancy | ✓ |
| Z3A.31 | 31 weeks gestation of pregnancy | ✓ |
| Z3A.31 | 31 weeks gestation of pregnancy | ✓ |
| Z3A.32 | 32 weeks gestation of pregnancy | ✓ |
| Z3A.32 | 32 weeks gestation of pregnancy | ✓ |
| Z3A.33 | 33 weeks gestation of pregnancy | ✓ |
| Z3A.33 | 33 weeks gestation of pregnancy | ✓ |
| Z3A.34 | 34 weeks gestation of pregnancy | ✓ |
| Z3A.34 | 34 weeks gestation of pregnancy | ✓ |
| Z3A.35 | 35 weeks gestation of pregnancy | ✓ |
| Z3A.35 | 35 weeks gestation of pregnancy | ✓ |
| Z3A.36 | 36 weeks gestation of pregnancy | ✓ |
| Z3A.36 | 36 weeks gestation of pregnancy | ✓ |
| Z3A.37 | 37 weeks gestation of pregnancy | ✓ |
| Z3A.37 | 37 weeks gestation of pregnancy | ✓ |
| Z3A.38 | 38 weeks gestation of pregnancy | ✓ |
| Z3A.38 | 38 weeks gestation of pregnancy | ✓ |
| Z3A.39 | 39 weeks gestation of pregnancy | ✓ |
| Z3A.39 | 39 weeks gestation of pregnancy | ✓ |
| Z3A.40 | 40 weeks gestation of pregnancy | ✓ |
| Z3A.40 | 40 weeks gestation of pregnancy | ✓ |
| Z3A.41 | 41 weeks gestation of pregnancy | ✓ |
| Z3A.41 | 41 weeks gestation of pregnancy | ✓ |
| Z3A.42 | 42 weeks gestation of pregnancy | ✓ |
| Z3A.42 | 42 weeks gestation of pregnancy | ✓ |
| Z3A.49 | Greater than 42 weeks gestation of pregnancy | ✓ |
| Z3A.49 | Greater than 42 weeks gestation of pregnancy | ✓ |
Frequently asked questions
What is ICD-10-CM code Z3A?
Z3A is an ICD-10-CM category covering Weeks of gestation. It contains 86 more specific diagnosis codes, 76 of which are billable.
Is Z3A a billable code?
No — Z3A 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 Z3A.0 — Weeks of gestation of pregnancy, unspecified or less than 10 weeks). 76 of the 86 codes under Z3A are billable.
What codes fall under Z3A?
Z3A includes Z3A.0, Z3A.0, Z3A.00, Z3A.00, Z3A.01, plus 81 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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