Table 1. Maternal characteristics according to severity of obesity.
| Reference women | Obese women | Obesity categories | |||||
| BMI 15.0–33.3 | BMI 32.6–64.4 | P * ′ | BMI 32.6–35 | BMI 35–37.5 | BMI≥37.5 | P * ′ | |
| Total population | 2450 | 2451 | 888 | 754 | 809 | ||
| Prepregnancy weight | |||||||
| Mean (sd) in kg | 66 (10.4) | 104 (12.5) | <0.01 | 96 (7.3) | 102 (7.8) | 116 (12.6) | <0.01 |
| Age at conception | % | % | % | % | % | ||
| <25 | 12.7 | 16.1 | 15.2 | 17.5 | 15.8 | ||
| 25–29 | 41.6 | 41.6 | 43.1 | 41.8 | 39.8 | ||
| 30–34 | 34.9 | 32.0 | 30.6 | 30.4 | 35.1 | ||
| 35+ | 10.8 | 10.2 | 0.02 | 11.0 | 10.3 | 9.3 | 0.03 |
| Parity | |||||||
| Primiparous | 50.1 | 47.5 | 52.5 | 43.2 | 45.9 | ||
| Multiparous | 49.9 | 52.6 | 0.03 | 47.5 | 56.8 | 54.1 | 0.03 |
| Height | |||||||
| <1.60 m | 4.7 | 6.9 | 6.6 | 7.0 | 7.1 | ||
| 1.60–1.69 m | 47.7 | 51.9 | 49.4 | 53.6 | 53.2 | ||
| 1.70 m+ | 47.6 | 41.2 | 0.03 | 43.9 | 39.4 | 39.8 | 0.03 |
| Gestational weight gain | |||||||
| <11kg | 17.0 | 59.2 | 52.4 | 59.3 | 66.4 | ||
| 11–19 kg | 59.2 | 30.8 | 35.8 | 31.5 | 24.9 | ||
| >19 kg | 23.8 | 10.0 | 0.02 | 11.9 | 9.2 | 8.8 | 0.04 |
| Smoking in pregnancy | |||||||
| Non smoker | 84.0 | 83.1 | 83.9 | 82.0 | 83.3 | ||
| 0–10 cig/day | 12.7 | 11.1 | 11.4 | 12.2 | 9.7 | ||
| >10 cig/day | 3.3 | 5.8 | 0.04 | 4.7 | 5.8 | 7.1 | 0.04 |
| Alcohol consumption | |||||||
| 0 shots/wk | 53.6 | 69.5 | 68.3 | 70.3 | 69.9 | ||
| 1/2–3 shots/wk | 43.8 | 29.7 | 30.3 | 29.1 | 29.7 | ||
| >3 shots/wk | 2.7 | 0.8 | 0.04 | 1.4 | 0.7 | 0.4 | 0.04 |
| Exercise in pregnancy | |||||||
| No exercise | 62.3 | 67.6 | 65.6 | 68.8 | 68.8 | ||
| 1–180 min/wk | 30.3 | 27.0 | 28.8 | 26.3 | 25.7 | ||
| 180 min+/wk | 7.4 | 5.4 | 0.03 | 5.6 | 4.9 | 5.6 | 0.03 |
| Social group | |||||||
| High | 54.9 | 33.0 | 35.2 | 33.5 | 30.2 | ||
| Middle | 36.0 | 48.7 | 49.5 | 47.5 | 48.9 | ||
| Low | 9.1 | 18.3 | 0.02 | 15.4 | 19.0 | 20.9 | 0.03 |
| Partners BMI | |||||||
| <18.5 | 0.5 | 0.9 | 1.0 | 1.1 | 0.6 | ||
| 18.5–24.9 | 53.5 | 36.9 | 39.7 | 37.3 | 33.5 | ||
| 25.0–29.9 | 39.7 | 43.1 | 42.4 | 42.5 | 44.4 | ||
| 30+ | 6.3 | 19.1 | 0.03 | 17.0 | 19.1 | 21.6 | 0.03 |
*
Tests for no association were for continuous variables T-test and ANOVA (analysis of variance), for categorical variables test for trend based on Goodman and Kruskal's gamma statistics. In tests applied to the 3 obesity groups, reference women were excluded.
Subjects with missing values: exercise, n = 38; gestational weight gain, n = 1781; paternal BMI, n = 1498. Missing for other variables, n<10.