Table 5. Relative risk of overweight at the age of 15 years according to the IOTF associated with pre-and perinatal risk indicators in the NFBC1966 and the NFBC1986.
| NFBC1966 (N = 1911) | NFBC1986 (N = 3709) | Total(N = 5620) | |||||||
| N | n(%) | RR(95%CI) | N | n(%) | RR(95%CI) | N | n(%) | RR(95%CI) | |
| Maternal BMI (kg/m2) | |||||||||
| <25 | 1456 | 104(7) | 1 | 3054 | 392(13) | 1 | 4510 | 496(11) | 1 |
| ≥25–<30 | 297 | 45(15) | 2.1(1.5–2.9) | 454 | 115(25) | 2.0(1.6–2.3) | 751 | 160(21) | 1.9(1.7–2.3) |
| ≥30 | 44 | 12(27) | 3.9(2.3–6.4) | 120 | 52(43) | 3.4(2.7–4.2) | 164 | 64(39) | 3.5(2.9–4.4) |
| Maternal smoking | |||||||||
| no | 1629 | 138(8) | 1 | 2205 | 439(15) | 1 | 4634 | 577(12) | 1 |
| 1–10 cigarettes/day | 210 | 24(11) | 1.3(0.9–2.0) | 303 | 61(20) | 1.4(1.1–1.8) | 513 | 85(17) | 1.3(1.1–1.6) |
| >10 cigarettes/day | 35 | 2(6) | 0.7(0.2–2.7) | 328 | 66(20) | 1.4(1.1–1.7) | 363 | 68(19) | 1.5(1.2–1.9) |
| Maternal cohabiting | |||||||||
| Cohabiting | 1857 | 161(9) | 1 | 3548 | 551(16) | 1 | 5405 | 712(13) | 1 |
| Single | 52 | 6(12) | 1.3(0.6–2.8) | 156 | 26(17) | 1.1(0.8–1.6) | 208 | 32(15) | 1.2(0.9–1.7) |
| Maternal age | |||||||||
| <25 | 832 | 74(9) | 1.3(0.9–1.7) | 1046 | 162(15) | 1.0(0.8–1.2) | 1878 | 236(13) | 1.0(0.9–1.2) |
| 25–35 | 848 | 60(7) | 1 | 2190 | 340(16) | 1 | 3038 | 400(13) | 1** |
| >35 | 228 | 32(14) | 2.0(1.3–3.0) | 473 | 75(16) | 1.0(0.8–1.3) | 701 | 107(15) | 1.2(1.0–1.5) |
| Long maternal education | |||||||||
| no | 1158 | 112(10) | 1 | 788 | 136(17) | 1 | 1946 | 248(13) | 1 |
| yes | 725 | 53(7) | 0.8(0.6–1.0) | 2504 | 390(16) | 0.9(0.8–1.1) | 3229 | 443(14) | 1.1(0.9–1.2) |
| Offspring gender | |||||||||
| Male | 920 | 70(8) | 1 | 1815 | 332(18) | 1 | 2735 | 4202(15) | 1** |
| Female | 991 | 97(10) | 1.3(1.0–1.7) | 1894 | 245(13) | 0.7(0.6–0.8) | 2885 | 342(12) | 0.8(0.7–0.9) |
| Birth weight (g) | |||||||||
| <50 percentile | 973 | 85(9) | 1 | 1872 | 236(13) | 1 | 2845 | 321(11) | 1 |
| ≥50–<75 | 491 | 38(8) | 0.9(0.6–1.3) | 932 | 153(16) | 1.3(1.0–1.5) | 1423 | 191(13) | 1.2(1.0–1.4) |
| ≥75–<90 | 266 | 25(9) | 1.1(0.7–1.7) | 556 | 104(19) | 1.4(1.1–1.7) | 822 | 129(16) | 1.4(1.1–1.6) |
| ≥90 | 181 | 19(11) | 1.3(0.8–2.0) | 349 | 84(24) | 1.8(1.4–2.2) | 530 | 103(19) | 1.7(1.4–2.0) |
| Offspring first born | |||||||||
| yes | 789 | 71(9) | 1 | 1229 | 198(16) | 1 | 2018 | 269(13) | 1 |
| no | 1119 | 96(9) | 1.0(0.7–1.3) | 2468 | 377(15) | 1.0(0.8–1.1) | 3587 | 473(13) | 1.0(0.9–1.1) |
No statistically significant differences between genders found.
**Statistically significant difference between cohorts. BMI- Body mass index. IOTF – overweight/obese according to the International Obesity Task Force. NFBC1966 and NFBC1986 – Northern Finnish Birth Cohorts born in 1966 and 1986.