Table 3. Diagnosis of ASD in Children According to Parental and Grandparental Age (Years) at Delivery.
| Variable | Children with ASD, No. | OR (95% CI) | ||
|---|---|---|---|---|
| Yes | No | Model 1 | Model 2 | |
| Maternal age, ya | ||||
| ≤19 | 419 | 19 005 | 0.92 (0.83-1.02) | 0.94 (0.84-1.05) |
| 20-24 | 3893 | 176 842 | 1.04 (1.00-1.08) | 1.05 (1.01-1.10) |
| 25-29 | 9353 | 498 454 | 1 [Reference] | 1 [Reference] |
| 30-34 | 9155 | 507 045 | 1.08 (1.04-1.11) | 1.04 (1.00-1.07) |
| 35-39 | 3960 | 211 177 | 1.22 (1.17-1.27) | 1.10 (1.05-1.15) |
| ≥40 | 836 | 36 644 | 1.56 (1.45-1.68) | 1.31 (1.21-1.42) |
| Paternal age, ya | ||||
| ≤19 | 120 | 5093 | 0.96 (0.80-1.15) | 1.00 (0.81-1.20) |
| 20-24 | 1886 | 85 626 | 1.02 (0.97-1.08) | 1.01 (0.95-1.07) |
| 25-29 | 7028 | 362 535 | 1 [Reference] | 1 [Reference] |
| 30-34 | 9464 | 526 094 | 1.02 (0.99-1.06) | 1.02 (0.98-1.05) |
| 35-39 | 5838 | 316 467 | 1.14 (1.10-1.19) | 1.11 (1.07-1.16) |
| 40-44 | 2322 | 111 036 | 1.35 (1.29-1.42) | 1.27 (1.20-1.34) |
| 45-49 | 693 | 31 262 | 1.46 (1.35-1.58) | 1.35 (1.24-1.47) |
| ≥50 | 265 | 11 054 | 1.57 (1.39-1.78) | 1.44 (1.27-1.64) |
| Maternal grandmother age, yb | ||||
| ≤19 | 601 | 23 418 | 1.68 (1.52-1.85) | 1.56 (1.39-1.74) |
| 20-24 | 2957 | 157 907 | 1.25 (1.18-1.33) | 1.22 (1.15-1.30) |
| 25-29 | 2681 | 176 418 | 1 [Reference] | 1 [Reference] |
| 30-34 | 1168 | 72 521 | 1.02 (0.95-1.10) | 1.01 (0.93-1.09) |
| 35-39 | 279 | 17 647 | 0.97 (0.85-1.10) | 0.96 (0.83-1.10) |
| ≥40 | 51 | 2586 | 1.13 (0.85-1.50) | 1.12 (0.83-1.52) |
| Maternal grandfather age, yb | ||||
| ≤19 | 141 | 5578 | 1.50 (1.26-1.78) | 1.20 (1.00-1.45) |
| 20-24 | 1800 | 88 583 | 1.22 (1.15-1.30) | 1.11 (1.04-1.18) |
| 25-29 | 3055 | 186 817 | 1 [Reference] | 1 [Reference] |
| 30-34 | 1813 | 114 277 | 0.96 (0.91-1.02) | 1.01 (0.94-1.08) |
| 35-39 | 654 | 38 889 | 0.99 (0.91-1.09) | 1.05 (0.95-1.16) |
| 40-44 | 184 | 11 451 | 0.91 (0.78-1.06) | 0.97 (0.82-1.14) |
| ≥45 | 90 | 4902 | 1.01 (0.82-1.25) | 1.07 (0.85-1.34) |
| Paternal grandmother age, yc | ||||
| ≤19 | 328 | 17 246 | 1.18 (1.04-1.34) | 1.13 (0.98-1.30) |
| 20-24 | 2012 | 121 846 | 1.08 (1.01-1.16) | 1.07 (0.99-1.15) |
| 25-29 | 2098 | 142 482 | 1 [Reference] | 1 [Reference] |
| 30-34 | 889 | 59 116 | 1.02 (0.94-1.10) | 1.00 (0.92-1.10) |
| 35-39 | 204 | 14 186 | 0.94 (0.81-1.10) | 0.91 (0.77-1.07) |
| ≥40 | 44 | 1987 | 1.40 (1.03-1.90) | 1.30 (0.93-1.80) |
| Paternal grandfather age, yc | ||||
| ≤19 | 73 | 3811 | 1.18 (0.93-1.50) | 1.11 (0.86-1.43) |
| 20-24 | 1185 | 68 816 | 1.11 (1.03-1.19) | 1.07 (0.99-1.16) |
| 25-29 | 2248 | 149 105 | 1 [Reference] | 1 [Reference] |
| 30-34 | 1385 | 91 618 | 1.02 (0.95-1.09) | 1.03 (0.96-1.11) |
| 35-39 | 459 | 30 769 | 0.99 (0.89-1.10) | 1.02 (0.91-1.15) |
| 40-44 | 161 | 9209 | 1.11 (0.94-1.31) | 1.14 (0.95-1.37) |
| ≥45 | 64 | 3535 | 1.12 (0.87-1.44) | 1.11 (0.84-1.46) |
Abbreviations: ASD, autism spectrum disorder; OR, odds ratio.
Model 1 was adjusted for child birth year, maternal parity, maternal education, and maternal country of origin. Model 2 was adjusted for child birth year, maternal parity, maternal education, maternal country of origin, and age of parent’s spouse.
Model 1 was adjusted for maternal birth year, parity of maternal grandmother, and education of maternal grandmother. Model 2 was adjusted for maternal birth year, parity of maternal grandmother, education of maternal grandmother, and age of maternal grandparent’s spouse.
Model 1 was adjusted for paternal birth year, parity of paternal grandmother, and education of paternal grandmother. Model 2 was adjusted for paternal birth year, parity of paternal grandmother, education of paternal grandmother, and age of paternal grandparent’s spouse.