Table 5.
Number and Percentage of Cases and Controls Missing Paternal Age, Categorized by Maternal Age, National Birth Defects Prevention Study 1997–2004.
| Maternal age | Case | Control | ||
|---|---|---|---|---|
| N | % | N | % | |
| 21 and under | 264 | 8.4 | 100 | 8.8 |
| 22–26 | 133 | 3.5 | 60 | 4.2 |
| 27–30 | 72 | 2.2 | 16 | 1.2 |
| 31–33 | 32 | 1.3 | 15 | 1.6 |
| 34 and over | 85 | 2.8 | 17 | 1.6 |
| Total | 586 | 3.7 | 208 | 3.6 |