Table 1.
Baseline characteristics in four prenatal cohorts from British Columbia, Ontario, Nova Scotia, and Newfoundland and Labrador
| BC | ON | NS | NL | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| All women | Nulliparous | Parous | All women | Nulliparous | Parous | All women | Nulliparous | Parous | All women | Nulliparous | Parous | |
| N (%) (and definition where applicable) | ||||||||||||
| BMI (kg/m2) | ||||||||||||
| Median (IQR) |
23.2 (20.8, 26.8) |
22.8 (20.6, 26.1) |
23.6 (21.1, 27.6) |
23.9 (21.1, 28.1) |
23.3 (20.8, 27.3) |
24.5 (21.5, 28.7) |
24.8 (21.7, 29.8) |
24.2 (21.5, 29.0) |
25.2 (21.9, 30.4) |
25.8 (22.4, 31.1) |
25.7 (22.2, 30.5) |
26.1 (22.7, 31.6) |
| Underweight | 1312 (6.0) | 752 (6.9) | 560 (5.1) | 5414 (5.8) | 2828 (7.0) | 2525 (4.8) | 224 (4.0) | 114 (4.4) | 110 (3.6) | 78 (3.4) | 42 (3.9) | 36 (2.9) |
| Normal weight | 12,887 (58.8) | 6756 (61.7) | 6131 (55.8) | 48,877 (52.2) | 22,401 (55.8) | 26,157 (49.2) | 2695 (48.1) | 1321 (51.2) | 1374 (45.5) | 962 (41.4) | 461 (42.8) | 501 (40.2) |
| Overweight | 4628 (21.1) | 2112 (19.3) | 2516 (22.9) | 22,449 (24.0) | 8675 (21.6) | 13,709 (25.8) | 1330 (23.7) | 591 (22.9) | 739 (24.5) | 590 (25.4) | 279 (25.9) | 311 (25.0) |
| Obese | 3103 (14.2) | 1324 (12.1) | 1779 (16.2) | 16,946 (18.1) | 6238 (15.5) | 10,752 (20.2) | 1353 (24.2) | 554 (21.5) | 799 (26.4) | 692 (29.8) | 295 (27.4) | 397 (31.9) |
| GWG < recommended | 4443 (20.3) | 1955 (17.9) | 2488 (22.6) | 18,087 (19.3) | 6391 (15.9) | 11,764 (22.1) | 1165 (20.8) | 430 (16.7) | 735 (24.3) | 358 (15.4) | 117 (10.9) | 241 (19.4) |
| GWG = recommended | 5676 (25.9) | 2835 (25.9) | 2841 (25.9) | 28,875 (30.8) | 11,650 (29.0) | 17,018 (32.0) | 1209 (21.6) | 534 (20.7) | 675 (22.3) | 440 (19.0) | 189 (17.6) | 251 (20.2) |
| GWG > recommended | 11,811 (53.9) | 6154 (56.2) | 5657 (51.5) | 46,724 (49.9) | 22,101 (55.1) | 24,361 (45.8) | 3228 (57.6) | 1616 (62.6) | 1612 (53.3) | 1524 (65.6) | 771 (71.6) | 753 (60.5) |
| Maternal age at birth (years) | ||||||||||||
| 19–24 | 2561 (11.7) | 1783 (16.3) | 778 (7.1) | 12,760 (13.6) | 7981 (19.9) | 4769 (9.0) | 1227 (21.9) | 767 (29.7) | 460 (15.2) | 436 (18.8) | 266 (24.7) | 170 (13.7) |
| 25–29 | 6188 (28.2) | 3609 (33.0) | 2579 (23.5) | 27,276 (29.1) | 14,111 (35.2) | 13,039 (24.5) | 1608 (28.7) | 810 (31.4) | 798 (26.4) | 770 (33.2) | 395 (36.7) | 375 (30.1) |
| 30–34 | 8091 (36.9) | 3767 (34.4) | 4324 (39.4) | 33,866 (36.2) | 12,963 (32.3) | 20,752 (39.1) | 1795 (32.0) | 728 (28.2) | 1067 (35.3) | 769 (33.1) | 312 (28.9) | 457 (36.7) |
| ≥ 35 | 5090 (23.2) | 1785 (16.3) | 3305 (30.1) | 19,784 (21.1) | 5087 (12.7) | 14,583 (27.4) | 972 (17.4) | 275 (10.7) | 697 (23.1) | 347 (14.9) | 104 (9.7) | 243 (19.5) |
| Nulliparous | 10,944 (49.9) | – | – | 40,155 (43.1) | – | – | 3022 (53.9) | – | – | 1077 (46.4) | – | – |
| Income | ||||||||||||
| QAIPPE = 5 | 3410 (15.6) | 1693 (15.5) | 1717 (15.6) | 14,989 (16.5) | 8019 (20.3) | 11,636 (22.3) | 691 ((15.1) | 295 (13.8) | 369 (16.3) | N/A | N/A | N/A |
| QAIPPE = 4 | 4467 (20.4) | 2174 (19.9) | 2293 (20.9) | 18,143 (20.0) | 8162 (20.7) | 10,259 (19.6) | 1040 (22.7) | 490 (22.8) | 440 (22.6) | N/A | N/A | N/A |
| QAIPPE = 3 | 4684 (21.4) | 2307 (21.1) | 2377 (21.6) | 18,862 (20.8) | 8414 (21.3) | 10,768 (20.6) | 1052 (23.0) | 512 (23.9) | 540 (22.2) | N/A | N/A | N/A |
| QAIPPE = 2 | 4837 (22.1) | 2456 (22.4) | 2381 (21.7) | 19,404 (21.4) | 8589 (21.8) | 11,387 (21.8) | 960 (21.0) | 464 (21.6) | 496 (20.4) | N/A | N/A | N/A |
| QAIPPE = 1 | 4532 (20.7) | 2314 (21.1) | 2218 (20.2) | 19,232 (21.2) | 6242 (15.8) | 8231 (15.7) | 836 (18.3) | 385 (17.9) | 451 (18.5) | N/A | N/A | N/A |
| Education | ||||||||||||
| Not graduated from high school | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 149 (6.4) | 48 (4.5) | 101 (8.1) |
| Graduated from high school | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 356 (15.3) | 151 (14.0) | 205 (16.5) |
| Beyond high school | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 158 (6.8) | 71 (6.6) | 87 (7.0) |
| College or university degree (including trade) | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 1598 (68.8) | 781 (72.5) | 817 (65.6) |
| Missing | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 61 (2.6) | 26 (2.4) | 35 (2.8) |
| Smoked | 1576 (7.2) | 715 (6.5) | 861 (7.8) | 10,000 (10.8) | 3995 (10.0) | 6015 (11.4) | 983 (17.6) | 376 (14.6) | 607 (20.2) | 335 (14.4) | 118 (11.0) | 217 (17.4) |
| Physical health conditions before pregnancy | ||||||||||||
| Hypertension | 132 (0.6) | 59 (0.5) | 73 (0.7) | 895 (1.0) | 356 (0.9) | 535 (1) | 71 (1.3) | 32 (1.2) | 39 (1.3) | 30 (1.3) | 16 (1.5%) | 14 (1.1%) |
| Diabetes (I or II) | 149 (0.7) | 69 (0.6) | 80 (0.7) | (901 (1.0) | 337 (0.9) | 566 (1.1) | 52 (0.9) | 22 (0.9) | 30 (1.0) | 34 (1.5) | 21 (1.9%) | 13 (1.0%) |
| Health conditions during pregnancy | ||||||||||||
| GDM | 2728 (12.4) | 1253 (11.4) | 1475 (13.4) | 5265 (5.8) | 2008 (5.2) | 3231 (6.3) | 371 (6.6) | 167 (6.5) | 204 (6.8) | 163 (7.0) | 70 (6.5) | 93 (7.5) |
| Preeclampsia | 417 (1.9)a | 285 (2.6)a | 132 (1.2)a | 682 (0.7) | 449 (1.1) | 229 (0.4) | 115 (2.1) | 91 (3.5) | 24 (0.8) | 47 (2.0) | 36 (3.3) | 11 (0.9) |
| Mental health conditions before or during pregnancy | ||||||||||||
| Depression | 2511 (11.4) | 1258 (11.5) | 1253 (11.4) | 8245 (8.9) | 3092 (7.7) | 5144 (9.7) | 408 (7.3) | 176 (6.8) | 232 (7.7) | b | b | b |
| Other | 1723 (7.9) | 794 (7.3) | 929 (8.5) | 5204 (5.6) | 2598 (6.5) | 2594 (4.9) | 476 (8.5) | 215 (8.3) | 261 (8.6) | 24 (1.0) | 17 (1.6) | 7 (0.6) |
| Gestational age at birth | ||||||||||||
| 22 + 0 to 33 + 6 | 372 (1.7) | 190 (1.7) | 182 (1.7) | 1045 (1.1) | 492 (1.2) | 522 (1) | 58 (1.0) | 32 (1.2) | 26 (0.9) | 24 (1.0) | 18 (1.7) | 6 (0.5) |
| 34 + 0 to 36 + 6 | 1440 (6.6) | 706 (6.4) | 734 (6.7) | 4172 (4.5) | 1856 (4.6) | 2304 (4.3) | 283 (5.1) | 140 (5.4) | 143 (4.7) | 106 (4.6) | 56 (5.2) | 50 (4.0) |
| 37 + 0 to 41 + 6 | 19,933 (90.9) | 9917 (90.6) | 10,016 (91.2) | 88,025 (94.0) | 37,491 (93.4) | 50,175 (94.4) | 5171 (92.3) | 2355 (91.3) | 2816 (93.2) | 2190 (94.3) | 1002 (93.0) | 1188 (95.4) |
| 42 + 0 to 42 + 6 | 185 (0.8) | 131 (1.2) | 54 (0.5) | 444 (0.5) | 303 (0.8%) | 142 (0.3) | 90 (1.6) | 53 (2.1) | 37 (1.2) | b | b | b |
| Birthweight (g) | ||||||||||||
| Mean (SD) | 3403 (534) | 3359 (535) | 3448 (528) | 3395 (548) | 3349 (535) | 3431 (552) | 3442 (534) | 3383 (524) | 3492 (539) | 3487 (532) | 3426 (561) | 3540 (500) |
| SGA (< 10%) | 1443 (6.6) | 955 (8.7) | 488 (4.4) | 8490 (9.1) | 4671 (11.6) | 3787 (7.1) | 432 (7.7) | 243 (9.4) | 189 (6.3) | 133 (5.7) | 74 (6.9) | 59 (4.7) |
| AGA (10–90%) | 17,535 (80.0) | 8896 (81.3) | 8639 (78.6) | 75,161 (80.4) | 32,343 (80.6) | 42,615 (80.2) | 4454 (79.5) | 2099 (81.4) | 2355 (77.9) | 1840 (79.2) | 883 (81.9) | 957 (76.9) |
| LGA (> 90%) | 2952 (13.5) | 1093 (10.0) | 1859 (16.9) | 9918 (10.6) | 3149 (7.8) | 6768 (12.7) | 716 (12.8) | 238 (9.2) | 478 (15.8) | 349 (15.0) | 120 (11.1) | 229 (18.4) |
Abbreviations: AGA, appropriate for gestational age; BC, British Columbia; BMI, body mass index; GDM, gestational diabetes mellitus; GWG, gestational weight gain; IQR, interquartile range; LGA, large for gestational age; N, number; NL, Newfoundland and Labrador; NS, Nova Scotia; ON, Ontario; QAIPPE, quintile of annual income per person equivalent; SD, standard deviation; SGA, small for gestational age
aGestational hypertension
bValues under 5 not displayed