Number of births (n) |
1994 | 1278 | 927 | 1630 | 248 | 849 | 4932 |
1995 | 1373 | 938 | 1643 | 303 | 803 | 5060 |
1996 | 1469 | 1057 | 1684 | 321 | 820 | 5351 |
1997 | 1282 | 1008 | 1715 | 334 | 921 | 5260 |
Total no. | 5402 | 3930 | 6672 | 1206 | 3393 | 20603 |
Mean maternal age (y) | 28.88 | 29.14 | 29.42 | 29.59 | 28.74 | 29.12 |
(SD) | (5.07) | (4.88) | (4.76) | (4.54) | (5.05) | (4.91) |
Parity (%) |
0 | 48.6 | 49.5 | 50.0 | 46.8 | 45.7 | 48.7 |
1 | 35.4 | 35.4 | 35.9 | 39.1 | 36.9 | 36.0 |
⩾2 | 16.0 | 15.1 | 14.1 | 14.1 | 17.4 | 15.3 |
Parity: χ2 test (p value) | 0.023 | 0.002 | 0.000 | 0.028 | reference | |
German women (%) | 66.4 | 73.1 | 80.4 | 86.6 | 75.4 | 74.9 |
Twin births (%) |
1994 | 1.0 | 1.4 | 1.5 | 0.8 | 0.8 | 1.2 |
1995 | 1.0 | 1.5 | 1.0 | 1.3 | 0.5 | 1.0 |
1996 | 1.6 | 2.1 | 1.5 | 0.9 | 0.7 | 1.5 |
1997 | 2.4 | 1.3 | 1.6 | 2.1 | 1.0 | 1.7 |
Total | 1.5 | 1.6 | 1.4 | 1.3 | 0.8 | 1.4 |
Total: χ2 test (p value) | 0.002 | 0.001 | 0.006 | 0.079 | reference | |
Triplet births (%) | – | 0.1 | 0.04 | – | – | 0 |