Table 1.
Characteristics of the Participating Cohorts
| Characteristics | Category | ABCD (N=8131) | ALSPAC (N=13 049) | BASELINE (N=1436) | BiB Study (N=12 799) | DNBC Study (N=89 107) | MoBa (N=101 975) | NINFEA Study (N=5893) |
|---|---|---|---|---|---|---|---|---|
| Country | The Netherlands | United Kingdom | Ireland | United Kingdom | Denmark | Norway | Italy | |
| Recruitment period | 2003–2004 | 1991–1992 | 2008–2011 | 2007–2011 | 1996–2002 | 1999–2008 | 2005–2016 | |
| Offspring | ||||||||
| CHD | Any | 34 (0.4) | 103 (0.8) | 10 (0.7) | 145 (1.1) | 1264 (1.4) | 879 (0.9) | 34 (0.6) |
| CHD severity in those with CHD | Nonsevere | … | 73/103 (70.9) | … | 93/145 (64.1) | 896/1264 (70.9) | … | 27/34 (79.4) |
| Severe | … | 30/103 (29.1) | … | 52/145 (35.9) | 368/1264 (29.1) | … | 7/34 (20.6) | |
| Chromosomal/genetic defects* | 26 (0.3) | 58 (0.4) | … | 198 (1.5) | 698 (0.8) | 169 (0.2) | 7 (0.1) | |
| Maternal | ||||||||
| Age, y | 30.7 (5.3) | 28.9 (4.8) | 30.7 (4.4) | 26.0 (5.7) | 29.9 (4.3) | 30.2 (4.6) | 33.1 (4.3) | |
| BMI, kg/m2 | 23.1 (4.1) | 22.6 (4.4) | 24.4 (4.1) | 26.0 (5.7) | 23.6 (4.3) | 24.0 (4.3) | 22.5 (3.8) | |
| BMI categories | Underweight (<18.5 kg/m2) | 360 (4.9) | 1271 (11.6) | 23 (1.6) | 444 (4.4) | 3861 (4.5) | 3077 (3.2) | 501 (8.5) |
| Normal (18.5–<25 kg/m2) | 5270 (71.8) | 7426 (67.7) | 914 (63.6) | 4586 (45.4) | 57 894 (67.8) | 63 706 (65.4) | 4156 (70.5) | |
| Overweight (25–<30 kg/m2) | 1245 (17.0) | 1537 (14.0) | 345 (24.0) | 2952 (29.2) | 16 578 (19.4) | 21 280 (21.8) | 826 (14.0) | |
| Obese (≥30 kg/m2) | 467 (6.4) | 736 (6.7) | 154 (10.7) | 2127 (21.0) | 7017 (8.2) | 9337 (9.6) | 286 (4.9) | |
| Pregnancy smoking | Yes† | 769 (9.5) | 3147 (24.7)† | 357 (24.9)† | 1788 (16.4) | 22 514 (26.0)† | 9650 (9.6) | 472 (8.1)† |
| Light | … | 1684 (15.7) | … | 1362 (12.5) | 15 777 (17.9) | 7856 (7.7) | 438 (7.5) | |
| Heavy | … | 1096 (10.2) | … | 426 (3.9) | 7431 (8.5) | 1587 (1.6) | 30 (0.5) | |
| Pregnancy alcohol | Yes† | 1686 (20.8) | 6894 (54.6)† | 527 (36.7) | … | 38 733 (44.7)† | 22 799 (27.7)† | 1508 (25.8)† |
| Light | … | 3044 (46.8) | … | … | 46 774 (52.9) | 10 461 (12.4) | 1416 (24.4) | |
| Moderat/heavy | … | 871 (13.4) | … | … | 3717 (4.2) | 509 (0.6) | 230 (3.9) | |
| Parity | Nulliparous | 4500 (55.3) | 5645 (45.0) | 1436 (100) | 4912 (39.8) | 42 203 (47.4) | 46 988 (46.9) | 4070 (72.4) |
| Education | Low | 4035 (49.6) | 2374 (20.0) | … | 5717 (56.9) | 22 225 (27.6) | 2735 (2.9) | 278 (4.8) |
| Medium | 2225 (27.4) | 7985 (67.1) | 208 (14.6) | 1563 (15.6) | 17 756 (22.0) | 31 430 (33.1) | 1892 (32.4) | |
| High | 1871 (23.0) | 1538 (12.9) | 1219 (85.4) | 2769 (27.6) | 40 675 (50.4) | 60 847 (64.0) | 3677 (62.9) | |
| Folic acid supplementation | Yes | 5677 (70.7) | 1070 (8.5) | … | … | 56 998 (69.0) | 74 466 (74.3) | 4741 (82.5) |
| Paternal | ||||||||
| Age, y | 35.1 (5.8) | 30.9 (5.8) | 32.2 (4.8) | 30.4 (6.6) | 32.2 (5.2) | 32.7 (5.4) | 36.2 (5.2) | |
| BMI, kg/m2 | 25.0 (3.5) | 25.2 (3.3) | 26.8 (3.6) | 26.8 (4.7) | 25.2 (3.2) | 25.8 (3.3) | 24.8 (3.2) | |
| BMI categories | Underweight (<18.5 kg/m2) | 28 (0.8) | 41 (0.5) | 2 (0.2) | 53 (1.9) | 271 (0.4) | 242 (0.2) | 43 (0.75) |
| Normal (18.5–<25 kg/m2) | 1966 (54.8) | 4308 (53.3) | 345 (30.9) | 953 (35.0) | 33 502 (53.5) | 42 952 (44.4) | 3332 (58.4) | |
| Overweight (25–<30 kg/m2) | 1372 (38.2) | 3111 (38.5) | 594 (53.3) | 1137 (41.7) | 24 529 (39.2) | 43 888 (45.3) | 1977 (34.6) | |
| Obese (≥30 kg/m2) | 223 (6.2) | 616 (7.6) | 174 (15.6) | 582 (21.4) | 4335 (6.9) | 9759 (10.1) | 355 (6.2) | |
| Smoking | Yes | … | 3459 (37.9) | 277 (24.9) | 1021 (32.0) | 26 242 (30.9) | 27 803 (27.3) | … |
| Alcohol | None | … | 449 (5.5) | … | … | … | 2963 (4.1) | … |
| Light drinking | … | 4251 (51.8) | … | … | … | 59 577 (82.3) | … | |
| Moderate/heavy drinking | … | 3505 (42.7) | … | … | … | 9882 (13.6) | … | |
| Education | Low | 190 (8.5) | 2959 (25.9) | … | 4299 (52.9) | 17 069 (21.8) | 4245 (4.4) | 956 (16.6) |
| Medium | 398 (17.9) | 6391 (55.9) | … | 1115 (13.7) | 28 230 (36.0) | 43 576 (45.1) | 2464 (42.8) | |
| High | 1670 (73.9) | 2079 (18.2) | … | 2709 (33.3) | 33 118 (42.2) | 48 782 (50.5) | 2335 (40.6) | |
Data are given as mean (SD) or number (percentage). Study numbers are based on singletons with data on at least one outcome and one exposure. Light smoking, <10 cigarettes per day; heavy smoking, ≥10 cigarettes per day; maternal light drinking, >0 and <3 units per week during pregnancy; maternal moderate/heavy drinking, ≥3 units per week during pregnancy; paternal light drinking, >0 and <7 units per week; paternal moderate/heavy drinking, ≥7 units per week. … Indicates data were not available; ABCD, The Amsterdam Born Children and Their Development Study; ALSPAC, Avon Longitudinal Study of Parents and Children; BASELINE, Cork Scope Baseline Study; BiB, Born in Bradford; BMI, body mass index; CHD, congenital heart disease; DNBC, Danish National Birth Cohort; MoBa, Norwegian Mother, Father and Child Cohort Study; and NINFEA, Nascita e Infanzia: gli Effetti dell'Ambiente (Birth and Childhood: Effects of the Environment).
Chromosomal/genetic/teratogenic anomalies with a cause thought to be already known (see Table S3 for classifications).
Denotes that the study had data specifically during the first trimester. Numbers in the moderate/heavy columns for smoking and alcohol do not add up to the number of any smoking/alcohol because some studies used trimester‐specific data for the binary data, whereas moderate/heavy is an assessment of the exposure throughout pregnancy.