Table 4. Relative risk of overweight at the age of 9 years according to the IOTF associated with pre- and perinatal risk indicators in the NFBC1966 and the NFBC1986.
| NFBC1966 (N = 1399) | NFBC1986 (N = 4064) | Total(N = 5463) | |||||||
| N | n(%) | RR(95%CI) | N | n(%) | RR(95%CI) | N | n(%) | RR(95%CI) | |
| Maternal BMI (kg/m2) | |||||||||
| <25 | 1042 | 83(8) | 1 | 3334 | 474(14) | 1 | 4376 | 557(13) | 1 |
| ≥25–<30 | 225 | 30(13) | 1.6(1.1–2.4) | 512 | 132(26) | 1.8(1.5–2.1) | 737 | 162(22) | 1.7(1.5–2.0) |
| ≥30 | 39 | 9(23) | 2.9(1.6–5.3) | 133 | 51(38) | 2.7(2.1–3.4) | 172 | 60(35) | 2.7(2.2–3.4) |
| Maternal smoking | |||||||||
| no | 1187 | 104(9) | 1 | 3275 | 489(15) | 1 | 4462 | 593(13) | 1 |
| 1–10 cigarettes/day | 159 | 16(10) | 1.2(0.7–1.9) | 338 | 77(23) | 1.5(1.2–1.9) | 497 | 93(19) | 1.4(1.2–1.7) |
| >10 cigarettes/day | 31 | 5(16) | 2.0(0.9–4.4) | 371 | 97(26) | 1.8(1.5–2.1) | 402 | 102(25) | 1.9(1.6–2.3) |
| Maternal cohabiting | |||||||||
| Cohabiting | 1358 | 120(9) | 1 | 3893 | 639(16) | 1 | 5251 | 759(14) | 1 |
| Single | 39 | 6(15) | 1.6(0.8–3.5) | 165 | 34(21) | 1.3(0.9–1.7) | 204 | 40(19) | 1.3(1.0–1.8) |
| Maternal age | |||||||||
| <25 | 597 | 58(10) | 1.3(0.9–1.8) | 1135 | 183(16) | 1.0(0.8–1.1) | 1732 | 241(14) | 0.9(0.8–1.1) |
| 25–35 | 611 | 46(8) | 1 | 2412 | 400(17) | 1 | 3023 | 446(15) | 1 |
| >35 | 190 | 23(12) | 1.6(1.0–2.6) | 517 | 90(17) | 1.1(0.9–1.3) | 707 | 113(16) | 1.1(0.9–1.3) |
| Long maternal education | |||||||||
| no | 858 | 76(9) | 1 | 859 | 160(19) | 1 | 1717 | 236(14) | 1 |
| yes | 525 | 50(10) | 1.1(0.8–1.5) | 2793 | 451(17) | 0.9(0.8–1.0) | 3259 | 501(15) | 1.1(1.0–1.3) |
| Offspring gender | |||||||||
| Male | 670 | 46(7) | 1 | 1999 | 325(16) | 1 | 2669 | 371(14) | 1** |
| Female | 729 | 81(11) | 1.6(1.1–2.3) | 2065 | 348(17) | 1.0(0.9–1.2) | 2794 | 429(15) | 1.1(1.0–1.3) |
| Birth weight (kg) | |||||||||
| <50 percentile | 708 | 65(9) | 1 | 2046 | 289(14) | 1 | 2754 | 354(13) | 1 |
| ≥50–<75 | 362 | 22(6) | 0.7(0.4–1.1) | 1002 | 154(15) | 1.1(0.9–1.3) | 1364 | 176(13) | 1.0(0.9–1.2) |
| ≥75–<90 | 187 | 24(13) | 1.5(0.9–2.3) | 620 | 124(20) | 1.4(1.2–1.7) | 807 | 148(18) | 1.5(1.2–1.7) |
| ≥90 | 142 | 16(11) | 1.3(0.8–2.2) | 396 | 106(27) | 1.9(1.6–2.4) | 538 | 122(23) | 1.8(1.5–2.2) |
| Offspring first born | |||||||||
| yes | 576 | 56(10) | 1 | 1341 | 246(18) | 1 | 1917 | 302(16) | 1 |
| no | 820 | 71(9) | 0.9(0.6–1.2) | 2712 | 425(16) | 0.9(0.9–1.0) | 3532 | 496(14) | 0.9(0.8–1.0) |
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.