Total | Underweight | Normal weight | Overweight | Obese I | Obese II | Obese III | ANOVA χ2 | ||
Pregnancies | n | 152 961 | 3147 | 74 041 | 45 098 | 19 097 | 7861 | 3717 | |
% | – | 2.06 | 48.41 | 29.48 | 12.48 | 5.14 | 2.43 | ||
Age (mean±SD, year) | 29.40±5.5 | 26.1±5.8 | 29.2±5.5 | 29.9±5.5 | 29.6±5.5 | 29.6±5.4 | 29.8±5.4 | p<0.001 | |
Age group (years) | |||||||||
13–19 | 6757 (4.4) | 487 (15.5) | 3845 (5.2) | 1539 (3.4) | 618 (3.2) | 192 (2.4) | 76 (2.0) | p<0.001 | |
20–29 | 68 470 (44.8) | 1724 (54.8) | 33 220 (44.9) | 19 340 (42.9) | 8767 (45.9) | 3720 (47.3) | 1699 (45.7) | ||
30–39 | 73 414 (48.0) | 909 (28.9) | 35 194 (47.5) | 22 756 (50.5) | 9067 (47.5) | 3679 (46.8) | 1809 (48.7) | ||
40+ | 4320 (2.8) | 27 (0.9) | 1782 (2.4) | 1463 (3.2) | 645 (3.4) | 270 (3.4) | 133 (3.6) | ||
Missing | 0 | – | – | – | – | – | – | ||
Self-reported employment | |||||||||
Yes | 112 269 (73.4) | 1826 (58.0) | 56 548 (76.4) | 34 355 (76.2) | 13 681 (71.6) | 5338 (67.9) | 2347 (63.1) | p<0.001 | |
No | 35 212 (23.0) | 1260 (40.0) | 16 336 (22.1) | 10 045 (22.3) | 5121 (26.8) | 2404 (30.6) | 1306 (35.1) | ||
Missing | 2394 (1.6) | 61 (1.9) | 1157 (1.6) | 698 (1.5) | 295 (1.5) | 119 (1.5) | 64 (1.7) | ||
Ethnicity | |||||||||
White | 121 227 (79.3) | 2504 (79.6) | 58 779 (79.4) | 35 570 (78.9) | 15 099 (79.1) | 6296 (80.1) | 2979 (80.1) | p<0.001 | |
Other | 3029 (2.0) | 122 (3.9) | 1527 (2.1) | 923 (2.0) | 325 (1.7) | 97 (1.2) | 35 (0.9) | ||
Unknown | 28 705 (18.8) | 521 (16.6) | 13 735 (18.6) | 8605 (19.1) | 3673 (19.2) | 1468 (18.7) | 703 (18.9) | ||
Missing | 0 (0) | – | – | – | – | – | – | ||
Previous births | |||||||||
0 | 59 112 (38.6) | 1515 (48.1) | 30 933 (41.8) | 16 401 (36.4) | 6483 (33.9) | 2639 (33.6) | 1141 (30.7) | p<0.001 | |
1 | 53 777 (35.2) | 1088 (34.6) | 25 661 (34.7) | 15 941 (35.3) | 6916 (36.2) | 2826 (35.9) | 1345 (36.2) | ||
≥2 | 39 422 (25.8) | 529 (16.8) | 17 111 (23.1) | 12 562 (27.9) | 5632 (29.5) | 2368 (30.1) | 1220 (32.8) | ||
Missing | 650 (0.4) | 15 (0.5) | 336 (0.5) | 194 (0.4) | 66 (0.3) | 28 (0.4) | 11 (0.3) | ||
Planned pregnancy | |||||||||
Yes | 110 668 (72.4) | 1833 (58.2) | 54 018 (73.0) | 33 258 (73.7) | 13 597 (71.2) | 5471 (69.6) | 2491 (67.0) | p<0.001 | |
No | 40 988 (26.8) | 1282 (40.7) | 19 362 (26.2) | 11 442 (25.4) | 5380 (28.2) | 2329 (29.6) | 1193 (32.1) | ||
Missing | 1305 (0.9) | 32 (1.0) | 661 (0.9) | 398 (0.9) | 120 (0.6) | 61 (0.8) | 33 (0.9) | ||
Alcohol | |||||||||
No | 151 991 (99.3) | 3127 (99.4) | 73 546 (99.3) | 44 783 (99.3) | 19 002 (99.5) | 7831 (99.6) | 3702 (99.6) | p<0.001 | |
Yes | 924 (0.6) | 18 (0.6) | 471 (0.6) | 302 (0.7) | 91 (0.5) | 27 (0.3) | 15 (0.4) | ||
Missing | 46 (0.03) | † | † | † | † | † | † | ||
Smoking* | |||||||||
Never | 7946 (64.0) | 144 (55.8) | 3811 (67.1) | 2389 (64.6) | 952 (58.2) | 457 (57.3) | 193 (56.3) | p<0.001 | |
No, stopped this pregnancy | 832 (6.7) | 20 (7.8) | 349 (6.14) | 230 (6.2) | 132 (8.1) | 76 (9.5) | 25 (7.3) | ||
No, stopped prior to this pregnancy | 1847 (14.9) | 29 (11.2) | 737 (13.0) | 593 (16.0) | 264 (16.1) | 148 (18.6) | 76 (22.2) | ||
Yes | 1790 (14.4) | 65 (25.2) | 783 (13.8) | 488 (13.2) | 288 (17.6) | 117 (14.7) | 49 (14.3) | ||
Missing | 140 546 | 2889 | 68 361 | 41 398 | 17 461 | 7063 | 3374 |
Underweight <18.5 kg/m2; normal weight 18.5–24.99 kg/m2; overweight 25.00–29.99 kg/m2; obese I 30.00–34.99 kg/m2; obese II 35.00–39.99 kg/m2; obese III ≥40 kg/m2.
†, Suppressed due to small numbers (<10) NB whole group frequencies are also suppressed in the case where subgroups have small counts; *, Smoking variable only available from September 2016 onwards, therefore percentages calculated based on non-missing values; ANOVA, analysis of variance.