Table 2. Summary results of the meta-analyses of the association between young and old father and birth defects.
| Birth defects | Paternal age(years) | Pooled estimate (with 95% CI) | Heterogeneity (I2) | Publication bias |
| Urogenital Abnormalities | NO | |||
| <20 | 1.50 (1.03-2.19) | 0.0% | ||
| ≥40 | 1.28 (1.07-1.52) | 0.0% | ||
| Digestive System Abnormalities | NO | |||
| <20 | 1.13(0.98-1.30) | 0.0% | ||
| ≥40 | 0.90(0.79-1.02) | 0.0% | ||
| Nervous System Malformations | NO | |||
| <20 | 1.23(0.94-1.60) | 36.5% | ||
| ≥40 | 1.12(0.97-1.30) | 33.5% | ||
| Cardiovascular Abnormalities | NO | |||
| <20 | 1.05 (0.96-1.16) | 2.1% | ||
| ≥40 | 1.10 (1.01-1.20) | 37.6% | ||
| Facial Deformities | NO | |||
| <20 | 1.14 (0.99-1.31) | 0.0% | ||
| ≥40 | 1.08 (1.00-1.17) | 0.0% | ||
| Musculoskeletal Abnormalities | YES | |||
| <20 | 1.15 (0.86-1.54) | 53.7% | ||
| ≥40 | 1.19 (0.99-1.42) | 41.4% | ||
| Chromosome Disorders | NO | |||
| <20 | 1.38 (1.01-1.89) | 52.6% | ||
| ≥40 | 1.30 (1.12-1.52) | 62.1% |