Table 1.
Characteristics of singleton pregnancies in Ontario, 1996 to 2006, n = 1 399 389
| Characteristic | Fiscal year; no. (%) of singleton deliveries* | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1996 131 746 |
1997 128 976 |
1998 126 841 |
1999 126 078 |
2000 122 019 |
2001 126 062 |
2002 123 502 |
2003 127 086 |
2004 127 610 |
2005 128 721 |
2006 130 748 |
|
| Maternal age, yr, mean (SD) | 28.9 (5.4) | 29.1 (5.5) | 29.1 (5.5) | 29.2 (5.5) | 29.3 (5.6) | 29.5 (5.5) | 29.6 (5.5) | 29.7 (5.5) | 29.7 (5.5) | 29.8 (5.5) | 29.8 (5.5) |
| 15–19 | 6 990 (5.3) | 6 577 (5.1) | 6 621 (5.2) | 6 010 (4.8) | 5 730 (4.7) | 5 519 (4.4) | 5 233 (4.2) | 5 148 (4.1) | 4 808 (3.8) | 4 834 (3.8) | 5 029 (3.8) |
| 20–24 | 20 683 (15.7) | 20 038 (15.5) | 19 990 (15.8) | 19 465 (15.4) | 18 762 (15.4) | 18 562 (14.7) | 17 959 (14.5) | 17 900 (14.1) | 17 861 (14.0) | 17 903 (13.9) | 18 480 (14.1) |
| 25–29 | 40 814 (31.0) | 39 576 (30.7) | 38 150 (30.1) | 37 795 (30.0) | 35 824 (29.4) | 36 829 (29.2) | 35 674 (28.9) | 36 675 (28.9) | 36 836 (28.9) | 36 796 (28.6) | 36 684 (28.1) |
| 30–34 | 43 346 (32.9) | 42 247 (32.8) | 40 707 (32.1) | 40 608 (32.2) | 39 271 (32.2) | 41 677 (33.1) | 41 188 (33.4) | 42 744 (33.6) | 43 201 (33.9) | 43 459 (33.8) | 43 874 (33.6) |
| 35–54 | 19 913 (15.1) | 20 538 (15.9) | 21 373 (16.9) | 22 200 (17.6) | 22 432 (18.4) | 23 475 (18.6) | 23 448 (19.0) | 24 619 (19.4) | 24 904 (19.5) | 25 729 (20.0) | 26 681 (20.4) |
| Income quintile† | |||||||||||
| Q1 (lowest) | 29 414 (22.3) | 28 376 (22.0) | 28 355 (22.4) | 28 492 (22.6) | 27 558 (22.6) | 27 491 (21.8) | 26 340 (21.3) | 26 341 (20.7) | 26 078 (20.4) | 25 995 (20.2) | 26 040 (19.9) |
| Q2 | 27 744 (21.1) | 26 978 (20.9) | 26 040 (20.5) | 25 659 (20.4) | 24 495 (20.1) | 24 986 (19.8) | 23 934 (19.4) | 24 477 (19.3) | 23 966 (18.8) | 24 249 (18.8) | 24 564 (18.8) |
| Q3 | 26 413 (20.0) | 25 542 (19.8) | 25 262 (19.9) | 24 704 (19.6) | 24 045 (19.7) | 24 732 (19.6) | 24 083 (19.5) | 24 725 (19.5) | 24 571 (19.3) | 24 522 (19.1) | 24 935 (19.1) |
| Q4 | 26 247 (19.9) | 26 191 (20.3) | 25 213 (19.9) | 23 807 (18.9) | 23 150 (19.0) | 25 045 (19.9) | 25 243 (20.4) | 26 137 (20.6) | 26 928 (21.1) | 27 208 (21.1) | 27 799 (21.3) |
| Q5 (highest) | 21 133 (16.0) | 21 196 (16.4) | 20 765 (16.4) | 20 400 (16.2) | 19 841 (16.3) | 20 798 (16.5) | 20 766 (16.8) | 22 048 (17.3) | 22 498 (17.6) | 23 197 (18.0) | 23 664 (18.1) |
| Rural place of residence | 17 565 (13.3) | 16 810 (13.0) | 16 072 (12.7) | 14 756 (11.7) | 14 094 (11.6) | 14 315 (11.4) | 13 792 (11.2) | 14 143 (11.1) | 13 929 (10.9) | 13 813 (10.7) | 14 167 (10.8) |
| Maternal comorbidities | |||||||||||
| Any hypertension | 5 691 (4.3) | 5 994 (4.6) | 5 592 (4.4) | 5 601 (4.4) | 5 598 (4.6) | 5 486 (4.4) | 5 743 (4.7) | 6 035 (4.7) | 6 210 (4.9) | 6 305 (4.9) | 6 189 (4.7) |
| Any diabetes mellitus | 6 688 (5.1) | 6 410 (5.0) | 6 331 (5.0) | 6 267 (5.0) | 6 433 (5.3) | 7 241 (5.7) | 7 495 (6.1) | 7 750 (6.1) | 8 685 (6.8) | 8 875 (6.9) | 9 596 (7.3) |
| Other comorbidity‡ | 4 169 (3.2) | 3 991 (3.1) | 3 998 (3.2) | 4 343 (3.4) | 4 161 (3.4) | 4 449 (3.5) | 4 038 (3.3) | 4 313 (3.4) | 4 001 (3.1) | 4 069 (3.2) | 4 202 (3.2) |
| Genetics consultation | 564 (0.4) | 698 (0.5) | 758 (0.6) | 884 (0.7) | 907 (0.7) | 969 (0.8) | 914 (0.7) | 920 (0.7) | 944 (0.7) | 953 (0.7) | 876 (0.7) |
| Amniocentesis | 1 488 (1.1) | 1 682 (1.3) | 1 861 (1.5) | 1 916 (1.5) | 1 852 (1.5) | 1 868 (1.5) | 1783 (1.4) | 1 723 (1.4) | 1 638 (1.3) | 1 592 (1.2) | 1 364 (1.0) |
| Pregnancy in prior 5 yr | |||||||||||
| None | 75 279 (57.1) | 74 231 (57.6) | 73 421 (57.9) | 74 089 (58.8) | 72 919 (59.8) | 75 287 (59.7) | 75 137 (60.8) | 77 816 (61.2) | 78 231 (61.3) | 77 758 (60.4) | 79 133 (60.5) |
| Without complications | 53 466 (40.6) | 51 459 (39.9) | 49 792 (39.3) | 48 139 (38.2) | 45 071 (36.9) | 46 584 (37.0) | 44 379 (35.9) | 45 273 (35.6) | 45 338 (35.5) | 46 784 (36.3) | 47 556 (36.4) |
| With complications§ | 3 001 (2.3) | 3 286 (2.5) | 3 628 (2.9) | 3 850 (3.1) | 4 029 (3.3) | 4 191 (3.3) | 3 986 (3.2) | 3 997 (3.1) | 4 041 (3.2) | 4 179 (3.2) | 4 059 (3.1) |
| High-risk pregnancy¶ | 20 634 (15.7) | 20 629 (16.0) | 20 596 (16.2) | 21 002 (16.7) | 21 050 (17.3) | 22 160 (17.6) | 22 060 (17.9) | 22 958 (18.1) | 23 888 (18.7) | 24 385 (18.9) | 25 178 (19.3) |
Note: Q = quintile, SD = standard deviation.
*
Unless indicated otherwise.
†
Income quintiles for each fiscal year do not sum to 100% because of missing data for up to 3% of patients.
‡
Thyroid disease, cardiac disease, rheumatologic disease, venous thromboembolism, renal disease, epilepsy or admission to hospital for supervision of high-risk pregnancy.
§
Defined as prior pregnancy associated with genetics consultation, amniocentesis, admission to hospital for supervision of high-risk pregnancy or pregnancy ending in stillbirth.
¶
Defined as any hypertension, any diabetes mellitus, any other comorbidity (as defined above), genetics consultation or amniocentesis during index pregnancy or history of pregnancy with complications (as defined above).