Table 1 General maternal and child characteristics according to children’s T-score categories of CPRS-R:S subscales at age 7 years.
T-score of CPRS-R:S subscales, n (%) | ||||||||
|---|---|---|---|---|---|---|---|---|
Oppositional | Cognitive problems/inattention | Hyperactivity | ADHD Index | |||||
< 65 | ≥ 65 | < 65 | ≥ 65 | < 65 | ≥ 65 | < 65 | ≥ 65 | |
n = 1112 (92.4) | n = 92 (7.6) | n = 1057 (87.8) | n = 147 (12.2) | n = 1035 (86) | n = 169 (14) | n = 1085 (90.4) | n = 115 (9.6) | |
Maternal characteristics | ||||||||
Age (years), mean (SD) | 30.8 (3.9) | 30.5 (3.6) | 30.9 (3.9) | 29.8 (4.3)† | 30.9 (3.9) | 30.2 (4.0)* | 30.9 (3.9) | 29.6 (4.3)† |
Pre-pregnancy BMI (kg/m2), mean (SD) | 23.4 (4.0) | 24.0 (4.7) | 23.3 (4.0) | 24.2 (4.4)* | 23.3 (3.9) | 24.1 (5.1)* | 23.3 (4.0) | 24.7 (4.6)† |
Ethnic group, n (%) | ||||||||
Caucasian | 1097 (98.6) | 90 (97.8) | 1042 (98.6) | 145 (98.6) | 1020 (98.5) | 167 (98.8) | 1075 (98.7) | 112 (97.4) |
Other | 15 (1.3) | 2 (2.2) | 15 (1.4) | 2 (1.4) | 15 (1.5) | 2 (1.2) | 14 (1.3) | 3 (2.6) |
Educational level, n (%) | ||||||||
Primary or less | 226 (20.3) | 28 (30.4) | 207 (19.7) | 47 (32.0) | 207 (20.0) | 47 (27.8) | 219 (20.1) | 35 (30.4) |
Secondary | 451 (40.6) | 39 (42.4) | 433 (40.9) | 57 (38.8) | 418 (40.4) | 72 (42.6) | 437 (40.1) | 53 (46.1) |
University | 435 (39.1) | 25 (27.2)* | 417 (39.4) | 43 (29.2)† | 410 (39.6) | 50 (29.6)* | 433 (39.8) | 27 (23.5)† |
Social class, n (%) | ||||||||
Low | 638 (58.4) | 59 (64.1) | 595 (56.3) | 102 (69.4) | 583 (56.5) | 112 (66.3) | 612 (56.2) | 85 (73.9) |
Medium | 200 (18.0) | 15 (16.3) | 190 (18.0) | 25 (17.0) | 183 (17.7) | 32 (18.9) | 199 (18.3) | 16 (13.9) |
High | 274 (24.6) | 18 (19.6) | 272 (25.7) | 20 (13.6)† | 267 (25.8) | 25 (15.8)† | 278 (25.5) | 14 (12.2)† |
Smoking during pregnancy, n (%) | ||||||||
Yes | 304 (27.3) | 36 (39.1)* | 289 (27.3) | 51 (34.7)* | 280 (27.1) | 60 (35.5)* | 292 (26.8) | 48 (41.7)† |
No | 808 (72.7) | 56 (61.9) | 768 (72.7) | 96 (65.3) | 755 (72.9) | 109 (65.5) | 797 (73.2) | 67 (58.3) |
Alcohol intake during pregnancy (g/d), mean (SD) | 0.31 (0.9) | 0.28 (0.7) | 0.32 (1.0) | 0.21 (0.5) | 0.29 (0.9) | 0.38 (1.1) | 0.31 (0.9) | 0.26 (0.7) |
Mode of delivery, n (%) | ||||||||
Eutocic | 690 (62.0) | 56 (60.9) | 660 (62.4) | 86 (58.5) | 647 (62.5) | 99 (58.6) | 680 (62.4) | 66 (58.4) |
Dystocic | 422 (38.0) | 36 (39.1) | 397 (37.6) | 61 (41.5) | 388 (37.5) | 70 (41.4) | 409 (37.6) | 49 (42.6) |
Parity, n (%) | ||||||||
Primiparous | 629 (56.6) | 51 (55.4) | 591 (55.9) | 89 (60.5) | 579 (55.9) | 101 (59.8) | 605 (55.5) | 75 (65.2) |
Multiparous | 483 (43.4) | 41 (44.6) | 466 (44.1) | 58 (39.5) | 456 (44.1) | 68 (40.2) | 484 (44.5) | 40 (34.8)* |
Breastfeeding (months), mean (SD) | 27.0 (19.8) | 26.2 (21.4) | 27.5 (19.8) | 22.9 (20.2)† | 27.7 (19.9) | 21.8 (19.8)† | 27.6 (19.9) | 20.6 (19.6)† |
Iron characteristics and other parameters | ||||||||
Haemoglobin (g/dL), mean (SD) | ||||||||
1st trimester | 12.9 (0.8) | 12.8 (0.8) | 12.9 (0.8) | 12.8 (0.9) | 12.9 (0.9) | 12.8 (0.9) | 12.8 (0.8) | 12.9 (0.9) |
3rd trimester | 11.6 (0.9) | 11.5 (1.0) | 11.6 (0.9) | 11.5 (1.0) | 11.6 (0.9) | 11.5 (1.0) | 11.6 (0.9) | 11.6 (0.9) |
Anaemia (Hb < 110 g/L), n (%) | ||||||||
1st trimester | 20 (2.0) | 2 (2.4) | 18 (1.9) | 4 (3.0) | 17 (1.8) | 5 (3.3) | 19 (1.9) | 3 (2.9) |
3rd trimester | 268 (25.6) | 25 (29.8) | 253 (25.5) | 40 (29.2) | 249 (25.7) | 44 (27.3) | 264 (25.8) | 29 (27.4) |
Ferritin levels (µg/L) at 1st period, median (IQR)€ | 29.0 (17.8, 45.9) | 26.8 (15.5, 42.0) | 28.7 (17.0, 45.5) | 30.9 (20.0, 46.4) | 28.9 (17.0, 45.8) | 29.0 (20.0, 44.4) | 28.6 (17.0, 45.2) | 31.1 (20.7, 47.8) |
Iron deficiency at 1st trimester, n (%) | ||||||||
Yes | 139 (12.5) | 10 (10.9) | 138 (13.1) | 11 (7.5) | 135 (13.0) | 14 (8.2) | 141 (13.0) | 8 (7.0) |
No | 973 (87.5) | 82 (89.1) | 919 (86.9) | 136 (92.5) | 900 (86.9) | 155 (91.7) | 948 (87.0) | 107 (93.0) |
Iron supplementation, n (%) | ||||||||
Yes | 584 (52.5) | 56 (60.9) | 553 (52.3) | 87 (59.2) | 543 (52.5) | 97 (57.4) | 572 (52.5) | 68 (59.1) |
No | 528 (47.5) | 36 (39.1) | 504 (47.7) | 60 (40.8) | 492 (47.5) | 72 (42.6) | 517 (47.5) | 47 (40.9) |
Total iron intake (mg/d), mean (SD) | 29.3 (27.3) | 32.9 (33.5) | 29.8 (28.2) | 27.6 (24.9) | 29.6 (28.3) | 28.9 (24.9) | 29.6 (27.8) | 29.1 (27.9) |
Total iron intake ≥ 27 mg/d, n (%) | ||||||||
Yes | 370 (33.2) | 37 (40.2) | 355 (33.6) | 52 (35.4) | 347 (33.5) | 60 (35.5) | 370 (34.0) | 37 (32.2) |
No | 742 (66.7) | 55 (59.8) | 702 (66.4) | 95 (64.6) | 688 (66.5) | 109 (64.5) | 719 (66.0) | 78 (67.8) |
CRP ≥ 0.65 mg/L at 1st trimester, n (%)⁋ | ||||||||
Yes | 182 (26.4) | 20 (33.3) | 180 (27.0) | 22 (27.2) | 175 (26.8) | 27 (28.1) | 176 (25.9) | 26 (37.7)* |
No | 507 (73.6) | 40 (66.7) | 488 (73.0) | 59 (72.8) | 478 (73.2) | 69 (71.9) | 504 (74.1) | 43 (62.3) |
Child characteristics | ||||||||
Children’s sex, n (%) | ||||||||
Female | 571 (51.3) | 26 (28.3) | 513 (48.5) | 84 (57.1) | 518 (50.1) | 79 (46.7) | 548 (50.3) | 49 (42.6) |
Male | 541 (48.6) | 66 (71.7)† | 544 (51.5) | 63 (42.9)* | 517 (49.9) | 90 (53.3) | 541 (49.7) | 66 (57.4) |
Age at delivery (weeks), mean (SD) | 39.8 (1.2) | 40.1 (1.2)* | 39.8 (1.2) | 40.1 (1.3)* | 39.8 (1.2) | 39.9 (1.2) | 39.8 (1.2) | 40.1 (1.3)* |
Birth weight (g), mean (SD) | 3336 (384) | 3309 (444) | 3333 (386) | 3344 (408) | 3347 (385) | 3256 (403)† | 3333 (382) | 3348 (449) |
Birth head circumference (cm), mean (SD) | 34.5 (1.2) | 34.3 (1.2) | 34.5 (1.2) | 34.4 (1.3) | 34.5 (1.2) | 34.2 (1.2)* | 34.5 (1.2) | 34.4 (1.3) |
Age at time of test (years), mean (SD) | 7.3 (0.5) | 7.3 (0.5) | 7.3 (0.5) | 7.3 (0.5) | 7.3 (0.5) | 7.2 (0.5)* | 7.3 (0.5) | 7.3 (0.5) |
BMI-for-age z-score at 7 years, mean (SD) | 0.80 (1.2) | 0.71 (1.4) | 0.77 (1.2) | 0.90 (1.3) | 0.80 (1.2) | 0.71 (1.3) | 0.77 (1.2) | 0.90 (1.4) |
