Table 1.
Maternal characteristics at first pregnancy by previous pregnancy complications, Western Australia 1980–2015
| Characteristics | Total | Preeclampsia | Previous PE | Gestational diabetes | |
| No previous PE | No previous GDM | Previous GDM | |||
| N=252 368 | N=2 28 407 | N=23 961 | N=245 764 | N=6604 | |
| Maternal age, years | |||||
| <20 | 43 473 (17.2) | 38 999 (17.1) | 4474 (18.7) | 43 035 (17.5) | 438 (6.6) |
| 20–24 | 57 209 (22.7) | 51 194 (22.4) | 6015 (25.1) | 56 334 (22.9) | 875 (13.2) |
| 25–29 | 87 480 (34.7) | 79 285 (34.7) | 8195 (34.2) | 85 233 (34.7) | 2247 (34.0) |
| 30–34 | 51 537 (20.4) | 47 291 (20.7) | 4246 (17.7) | 49 332 (20.1) | 2205 (33.4) |
| ≥35 | 12 669 (5.0) | 11 638 (5.1) | 1031 (4.3) | 11 830 (4.8) | 839 (12.7) |
| Time period | |||||
| 1980–1984 | 32 982 (13.1) | 29 087 (12.7) | 3895 (16.3) | 32 940 (13.4) | 42 (0.6) |
| 1985–1989 | 35 703 (14.1) | 31 397 (13.7) | 4306 (18.0) | 35 583 (14.5) | 120 (1.8) |
| 1990–1994 | 36 940 (14.6) | 32 881 (14.4) | 4059 (16.9) | 36 492 (14.8) | 448 (6.8) |
| 1995–1999 | 37 012 (14.7) | 32 715 (14.3) | 4297 (17.9) | 36 070 (14.7) | 942 (14.3) |
| 2000–2004 | 37 260 (14.8) | 33 998 (14.9) | 3262 (13.6) | 36 031 (14.7) | 1229 (18.6) |
| 2005–2009 | 43 151 (17.1) | 40 458 (17.7) | 2693 (11.2) | 41 303 (16.8) | 1848 (28.0) |
| 2010–2015 | 29 320 (11.6) | 27 871 (12.2) | 1449 (6.0) | 27 345 (11.1) | 1975 (29.9) |
| SES in quintiles | |||||
| <20th percentile (Most disadvantaged) | 46 991 (18.6) | 42 087 (18.4) | 4904 (20.5) | 45 883 (18.7) | 1108 (16.8) |
| 20–39th percentile | 51 517 (20.4) | 46 271 (20.3) | 5246 (21.9) | 50 295 (20.5) | 1222 (18.5) |
| 40–59th percentile | 52 503 (20.8) | 47 506 (20.8) | 4997 (20.9) | 51 107 (20.8) | 1396 (21.1) |
| 60–79th percentile | 51 922 (20.6) | 47 140 (20.6) | 4782 (20.0) | 50 462 (20.5) | 1460 (22.1) |
| ≥80th percentile (least disadvantaged) | 49 435 (19.6) | 45 403 (19.9) | 4032 (16.8) | 48 017 (19.5) | 1418 (21.5) |
| Marital status | |||||
| Married | 215 196 (85.3) | 194 800 (85.3) | 20 396 (85.1) | 209 351 (85.2) | 5845 (88.5) |
| Others | 37 172 (14.7) | 33 607 (14.7) | 3565 (14.9) | 36 413 (14.8) | 759 (11.5) |
| Race/ethnicity | |||||
| Caucasian | 219 562 (87.0) | 198 137 (86.7) | 21 425 (89.4) | 214 645 (87.3) | 4917 (74.5) |
| Interpregnancy interval, months | |||||
| <6 | 12 104 (4.8) | 11 006 (4.8) | 1098 (4.6) | 11 780 (4.8) | 324 (4.9) |
| 6–11 | 42 470 (16.8) | 38 678 (16.9) | 3792 (15.8) | 41 267 (16.8) | 1203 (18.2) |
| 12–17 | 55 218 (21.9) | 50 237 (22.0) | 4981 (20.8) | 53 737 (21.9) | 1481 (22.4) |
| 18–23 | 42 934 (17.0) | 38 880 (17.0) | 4054 (16.9) | 41 751 (17.0) | 1183 (17.9) |
| 24–59 | 79 950 (31.7) | 71 980 (31.5) | 7970 (33.3) | 77 890 (31.7) | 2060 (31.2) |
| ≥60 | 19 692 (7.8) | 17 626 (7.7) | 2066 (8.6) | 19 339 (7.9) | 353 (5.3) |
| Partner change * | |||||
| Yes | 15 789 (6.3) | 14 307 (6.3) | 1482 (6.2) | 15 572 (6.3) | 217 (3.3) |
| Smoking | |||||
| Yes | 17 239 (13.6) | 16 062 (13.7) | 1177 (12.7) | 16 705 (13.8) | 534 (9.6) |
| Fertility treatment | |||||
| Yes | 4185 (2.7) | 3872 (2.7) | 313 (2.4) | 3882 (2.6) | 303 (4.9) |
Data are presented in n(%) based on study cohort that consists of first two pregnancies.
*Measured at second pregnancy.
GDM, gestational diabetes; PE, preeclampsia.