Table 1 Distribution of maternal age among singleton births, by cohort study
1982 | 1993 | 2004 | Pooled cohorts | |
|---|---|---|---|---|
N (%) | N (%) | N (%) | N (%) | |
Maternal age, y | ||||
12-15 | 65 (1.1) | 108 (2.1) | 114 (2.7) | 287 (1.9) |
16-17 | 296 (5.0) | 325 (6.2) | 289 (6.9) | 910 (5.9) |
18-19 | 556 (9.4) | 485 (9.3) | 400 (9.5) | 1,441 (9.4) |
20-29 | 3,424 (58.0) | 2,779 (53.2) | 2,084 (49.6) | 8,287 (54.1) |
30-39 | 1,424 (24.1) | 1,406 (26.9) | 1,172 (27.9) | 4,002 (26.1) |
40-49 | 143 (2.4) | 119 (2.3) | 140 (3.3) | 402 (2.6) |
Total | 5,908 (100) | 5,222 (100) | 4,199 (100) | 15,329 (100) |
Number of mothers less than 30 y | 4,341 | 3,697 | 2,887 | 10,925 |