Table 1. Total number and prevalence (1/10,000) of birth defects by gestational weeks and system in 5 counties, Shanxi Province, China, 2000−2019.
| ICD-10 code | Classification | Gestational weeks | ||
| <28 weeks | ≥28 weeks | Total | ||
| *The number of cases in this table was based on birth defect phenotypes, not the person. One person may have one more birth defects, so the total number of birth defects was greater than the cases. | ||||
| 1. Q00–Q07 | The nervous system | 1,987 (67.68) | 1,206 ( 41.08) | 3,193 (108.76) |
| 2. Q10–Q18 | Eye, ear, face and neck | 1 ( 0.03) | 139 ( 4.73) | 140 ( 4.77) |
| 3. Q20–Q28 | The circulatory system | 33 ( 1.12) | 51 ( 1.74) | 84 ( 2.86) |
| 4. Q35–Q37 | Cleft lip and cleft palate | 81 ( 2.76) | 614 ( 20.91) | 695 ( 23.67) |
| 5. Q38–Q45 | The digestive system | 4 ( 0.14) | 119 ( 4.05) | 123 ( 4.19) |
| 6. Q50–Q56 | Genital organs | 0 | 79 ( 2.69) | 79 ( 2.69) |
| 7. Q60–Q64 | The urinary system | 3 ( 0.10) | 7 ( 0.24) | 10 ( 0.34) |
| 8. Q65–Q79 | The musculoskeletal system | 122 ( 4.16) | 816 ( 27.80) | 938 ( 31.95) |
| 9. Q80–Q89 | Other congenital malformations | 181 ( 6.17) | 381 ( 12.98) | 562 ( 19.14) |
| 10. Q90–Q99 | Chromosomal abnormalities | 16 ( 0.55) | 5 ( 0.17) | 21 ( 0.72) |
| Total* | 2,428 (82.71) | 3,417 (116.39) | 5,845 (199.10) | |