Baseline characteristics of pregnant women in Ontario with and without an emergency department visit during pregnancy or up to 42 days postpartum, Apr. 1, 2002, to Mar. 31, 2017
| Characteristic | No. (%) of women* | SDiff | |
|---|---|---|---|
| Any peripregnancy emergency department visit n = 1 075 991 | No peripregnancy emergency department visit n = 1 652 245 | ||
| At start of pregnancy | |||
| Age, yr, mean ± SD | 28.6 ± 6.3 | 29.4 ± 5.9 | 0.13 |
| Age group, yr | |||
| 10–19 | 87 466 (8.1) | 99 890 (6.0) | 0.08 |
| 20–24 | 201 922 (18.8) | 243 707 (14.8) | 0.10 |
| 25–29 | 304 324 (28.3) | 457 282 (27.7) | 0.01 |
| 30–34 | 290 357 (27.0) | 526 941 (31.9) | 0.11 |
| 35–39 | 147 461 (13.7) | 261 792 (15.8) | 0.06 |
| 40–44 | 39 497 (3.7) | 56 970 (3.4) | 0.01 |
| 45–55 | 4964 (0.5) | 5663 (0.3) | 0.02 |
| Parity | |||
| Median (IQR) | 1.0 (0.0–1.0) | 1.0 (0.0–1.0) | 0.06 |
| 0 | 346 360 (32.2) | 591 500 (35.8) | 0.08 |
| 1 | 241 345 (22.4) | 498 319 (30.2) | 0.18 |
| 2 | 99 127 (9.2) | 192 334 (11.6) | 0.08 |
| ≥3 | 52 969 (4.9) | 92 190 (5.6) | 0.03 |
| Missing | 336 190 (31.2) | 277 902 (16.8) | 0.34 |
| Residential income quintile | |||
| 1 (lowest) | 278 342 (25.9) | 373 190 (22.6) | 0.08 |
| 2 | 225 928 (21.0) | 335 965 (20.3) | 0.02 |
| 3 | 213 068 (19.8) | 331 653 (20.1) | 0.01 |
| 4 | 200 811 (18.7) | 331 749 (20.1) | 0.04 |
| 5 (highest) | 152 539 (14.2) | 274 042 (16.6) | 0.07 |
| Missing | 5303 (0.5) | 5646 (0.3) | 0.02 |
| Rural residence | 147 290 (13.7) | 113 739 (6.9) | 0.23 |
| Foreign-born | 241 984 (22.5) | 501 151 (30.3) | 0.18 |
| Antenatal care provider in pregnancy | |||
| Obstetrician | 572 077 (53.2) | 1 000 313 (60.5) | 0.15 |
| Family physician/nurse practitioner | 180 902 (16.8) | 223 570 (13.5) | 0.09 |
| Other | 260 (0.0) | 154 (0.0) | 0.01 |
| None/unknown | 322 752 (30.0) | 428 208 (25.9) | 0.09 |
| No. of Johns Hopkins ADGs within 120 d before start of pregnancy | |||
| ≤ 2 | 753 609 (70.0) | 1 319 263 (79.8) | 0.23 |
| 3–4 | 217 573 (20.2) | 254 062 (15.4) | 0.13 |
| 5–6 | 76 152 (7.1) | 63 630 (3.9) | 0.14 |
| 7–32 | 28 657 (2.7) | 15 290 (0.9) | 0.13 |
| At end of pregnancy | |||
| Multiple birth† | 15 994 (2.3) | 20 307 (1.6) | 0.05 |
| No. of weeks of gestation at birth, mean ± SD† | 38.6 ± 2.4 | 38.9 ± 1.9 | 0.13 |
| Preterm birth at 20–36 weeks’ gestation† | 67 526 (9.6) | 80 728 (6.4) | 0.12 |
| Outcome of pregnancy | |||
| Livebirth at ≥ 20 weeks’ gestation | 701 370 (65.2) | 1 257 836 (76.1) | 0.24 |
| Stillbirth at ≥ 20 weeks’ gestation | 5422 (0.5) | 6030 (0.4) | 0.02 |
| Miscarriage at < 20 weeks’ gestation | 163 747 (15.2) | 58 433 (3.5) | 0.41 |
| Induced abortion at any gestational week | 64 599 (6.0) | 304 606 (18.4) | 0.39 |
| Threatened abortion at < 20 weeks’ gestation | 140 853 (13.1) | 25 340 (1.5) | 0.46 |