Perinatal Factors Potentially Associated With Weight Status at ≥24 Months of Age or With Antibiotic Exposure in Infancy
| Factor | Underweight or Normal Weight | Overweight or Obese | P | Unexposed | Exposed | P |
|---|---|---|---|---|---|---|
| Boys | ||||||
| n | 4738 | 1376 | 1286 | 4828 | ||
| Maternal age, y | NS | NS | ||||
| <30 | 1922 (40.6) | 555 (40.3) | 539 (41.9) | 1939 (40.1) | ||
| ≥30 | 2816 (59.4) | 821 (59.7) | 747 (58.1) | 2889 (59.9) | ||
| Maternal smoking after first trimestera | <0.01 | NS | ||||
| No | 4319 (91.2) | 1221 (88.7) | 1163 (90.4) | 4378 (90.7) | ||
| Yes | 289 (6.1) | 113 (8.2) | 77 (6.0) | 324 (6.7) | ||
| Maternal relationshipa | 0.001 | <0.05 | ||||
| Partner | 4358 (92.0) | 1238 (90.0) | 1154 (89.7) | 4451 (92.2) | ||
| Single | 263 (5.6) | 109 (7.9) | 93 (7.2) | 270 (6.0) | ||
| Gestational age, wks | NS | NS | ||||
| <40 | 2290 (48.3) | 642 (46.7) | 623 (48.4) | 2310 (47.9) | ||
| ≥40 | 2448 (51.7) | 734 (53.3) | 663 (51.6) | 2518 (52.1) | ||
| Mode of delivery | <0.05 | NS | ||||
| Vaginal | 3971 (83.8) | 1118 (81.3) | 1078 (83.8) | 4013 (83.1) | ||
| Cesarean | 767 (16.2) | 258 (18.8) | 208 (16.2) | 815 (16.9) | ||
| Parity | NS | <0.001 | ||||
| 0 sibling | 2282 (48.2) | 640 (46.5) | 709 (55.1) | 2213 (45.8) | ||
| ≥1 siblings | 2256 (51.8) | 736 (53.5) | 577 (44.9) | 2615 (54.2) | ||
| Plurality | NS | NS | ||||
| Singleton | 4638 (97.9) | 1351 (98.2) | 1259 (98.0) | 4730 (98.0) | ||
| Twin | 100 (2.1) | 25 (1.8) | 27 (2.0) | 98 (2.0) | ||
| Season at birth | NS | NS | ||||
| Spring or summer | 2035 (43.0) | 556 (40.4) | 553 (43.0) | 2037 (42.2) | ||
| Autumn or winter | 2703 (57.0) | 820 (59.6) | 733 (57.0) | 2791 (57.8) | ||
| Birth size, weightb | <0.001 | NS | ||||
| AGA | 4541 (95.8) | 1310 (95.2) | 1224 (95.2) | 4628 (95.9) | ||
| SGA | 129 (2.7) | 15 (1.1) | 36 (2.8) | 105 (2.2) | ||
| LGA | 68 (1.4) | 51 (3.7) | 26 (2.0) | 95 (1.9) | ||
| Birth size, lengthb | <0.001 | NS | ||||
| AGA | 4532 (95.7) | 1288 (93.6) | 1230 (95.6) | 4589 (95.1) | ||
| SGA | 101 (2.1) | 21 (1.5) | 28 (2.2) | 95 (1.9) | ||
| LGA | 105 (2.2) | 67 (4.9) | 28 (2.2) | 144 (3.0) | ||
| Exposure to antibiotics at <24 mo | <0.05 | — | ||||
| No | 1031 (21.8) | 255 (18.2) | 1286 (100) | 0 | ||
| Yes | 3707 (78.2) | 1121 (81.5) | 0 | 4828 (100) | ||
| Girls | ||||||
| n | 5230 | 718 | 1540 | 4408 | ||
| Maternal age, years | NS | <0.05 | ||||
| <30 y | 2182 (41.7) | 291 (40.5) | 664 (43.2) | 1810 (41.1) | ||
| ≥30 y | 3048 (58.3) | 427 (59.5) | 876 (56.8) | 2598 (58.9) | ||
| Maternal smoking after first trimesterc | <0.001 | NS | ||||
| No | 4770 (91.2) | 630 (87.7) | 1399 (90.8) | 4001 (90.8) | ||
| Yes | 324 (6.2) | 71 (9.9) | 88 (5.7) | 307 (7.0) | ||
| Maternal relationshipc | NS | NS | ||||
| Partner | 4767 (91.1) | 646 (90.0) | 1382 (89.7) | 4039 (91.6) | ||
| Single | 336 (6.4) | 52 (7.2) | 107 (6.9) | 273 (6.2) | ||
| Gestational age, weeks | NS | NS | ||||
| <40 | 2344 (44.8) | 321 (44.7) | 696 (45.2) | 1969 (44.7) | ||
| ≥40 | 2886 (55.2) | 397 (55.3) | 844 (54.8) | 2439 (55.3) | ||
| Mode of delivery | <0.05 | NS | ||||
| Vaginal | 4414 (84.4) | 584 (81.3) | 1299 (84.4) | 3702 (84.0) | ||
| Cesarean section | 816 (15.6) | 134 (18.7) | 241 (15.6) | 706 (16.0) | ||
| Parity | NS | <0.001 | ||||
| 0 sibling | 2487 (47.6) | 340 (47.4) | 825 (53.6) | 2001 (45.4) | ||
| ≥1 siblings | 2743 (52.4) | 378 (52.6) | 715 (46.4) | 2407 (54.6) | ||
| Plurality | NS | NS | ||||
| Singleton | 5127 (98.0) | 709 (98.7) | 1514 98.4) | 4323 (98.1) | ||
| Twin | 103 (2.0) | 9 (1.3) | 26 (1.6) | 85 (1.9) | ||
| Season at birth | NS | NS | ||||
| Spring or summer | 2212 (42.3) | 312 (43.5) | 660 (42.8) | 1864 (42.3) | ||
| Autumn or winter | 3018 (57.7) | 406 (56.5) | 880 (57.2) | 2544 (57.7) | ||
| Birth size / wtb | <0.001 | <0.05 | ||||
| AGA | 4999 (95.6) | 678 (94.4) | 1480 (96.2) | 4196 (95.2) | ||
| SGA | 103 (2.0) | 6 (0.8) | 29 (1.9) | 79 (1.8) | ||
| LGA | 128 (2.4) | 34 (4.7) | 31 (2.0) | 133 (3.0) | ||
| Birth size / lengthb | NS | NS | ||||
| AGA | 4976 (95.1) | 685 (95.4) | 1465 (95.2) | 4195 (95.2) | ||
| SGA | 100 (1.9) | 7 (1.0) | 29 (1.8) | 80 (1.8) | ||
| LGA | 154 (3.0) | 26 (3.6) | 46 (3.0) | 133 (3.0) | ||
| Exposure to antibiotics < 24 mo | NS | — | ||||
| No | 1374 (26.3) | 166 (23.1) | 1540 (100) | 0 | ||
| Yes | 3856 (73.3) | 552 (76.9) | 0 | 4408 (100) |
Values are expressed as n (%). AGA, appropriate for gestational age; LGA, large for gestational age; NS, statistically nonsignificant; SGA, small for gestational age. —, indicates P value is not available.
↵a Not available: maternal smoking n = 172; maternal relationship n = 146.
↵b Finnish growth reference for birth size.20
↵c Not available: maternal smoking n = 153; maternal relationship n = 147.