| Source ICD-10 | Mapping Type | Target ICD-9 |
| Recommended Mapping (based on statistical analysis) |
| O6023X0 (Diagnosis) - Term delivery w preterm labor, third trimester, unsp (Term delivery with preterm labor, third trimester, not applicable or unspecified) | Single To Single | 64421 (Diagnosis) - Early onset delivery-del (Early onset of delivery, delivered, with or without mention of antepartum condition) |
| CMS/CDC General Equivalence Mappings |
| O6023X0 (Diagnosis) - Term delivery w preterm labor, third trimester, unsp (Term delivery with preterm labor, third trimester, not applicable or unspecified) | Single To Single | Alternative #1: 64421 (Diagnosis) - Early onset delivery-del (Early onset of delivery, delivered, with or without mention of antepartum condition) |