Table 3.
Relationships between pre-pregnancy BMI and outcomes.
| Outcomes | Unadjusted RR | Adjusted RR* | ||
|---|---|---|---|---|
| OR (95% CI) | P | AOR (95% CI) | P | |
| GHD | ||||
| BMI < 18.5 kg/m2 | 0.84 (0.75–0.94) | 0.003 | 0.85 (0.75–0.95) | 0.005 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.26 (0.94–1.69) | 0.122 | 1.28 (1.16–1.43) | 0.004 |
| BMI ≥ 28.0 kg/m 2 | 2.51 (2.22–2.89) | 0.001 | 2.47 (2.24–2.74) | < 0.001 |
| GDM | ||||
| BMI < 18.5 kg/m2 | 0.66 (0.55–0.79) | < 0.001 | 0.69 (0.58–0.84) | < 0.001 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | |||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.52 (1.27–1.83) | < 0.001 | 1.63 (1.35–1.93) | < 0.001 |
| BMI ≥ 28.0 kg/m 2 | 3.06 (2.36–3.98) | 0.002 | 3.02 (2.12–3.79) | < 0.001 |
| Preterm birth | ||||
| BMI < 18.5 kg/m2 | 1.02 (0.96–1.08) | 0.554 | 1.42 (1.26–1.60) | 0.193 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.22 (1.15–1.29) | < 0.001 | 1.18 (1.11–1.25) | < 0.001 |
| BMI ≥ 28.0 kg/m 2 | 1.54 (1.38–1.71) | < 0.001 | 1.47 (1.32–1.64) | < 0.001 |
| LBW | ||||
| BMI < 18.5 kg/m2 | 1.20 (1.08–1.32) | < 0.001 | 1.25 (1.12–1.38) | 0.024 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 0.89 (0.76–1.01) | 0.192 | 0.90 (0.78–1.02) | 0.201 |
| BMI ≥ 28.0 kg/m 2 | 0.98 (0.86–1.12) | 0.746 | 0.92 (0.80–1.05) | 0.206 |
| Macrosomia | ||||
| BMI < 18.5 kg/m2 | 0.67 (0.62–0.73) | < 0.001 | 0.67 (0.62–0.73) | < 0.001 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.52 (1.43–1.61) | < 0.001 | 1.51 (1.42–1.60) | < 0.001 |
| BMI ≥ 28.0 kg/m 2 | 2.10 (1.89–2.34) | < 0.001 | 2.11 (1.90–2.35) | < 0.001 |
| SGA | ||||
| BMI < 18.5 kg/m2 | 1.12 (1.09–1.4) | < 0.001 | 1.11 (1.09–1.14) | < 0.001 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 0.90 (0.86–0.95) | < 0.001 | 0.91 (0.89–0.93) | < 0.001 |
| BMI ≥ 28.0 kg/m 2 | 0.91 (0.89–0.93) | < 0.001 | 0.90 (0.86–0.94) | < 0.001 |
| LGA | ||||
| BMI < 18.5 kg/m2 | 0.87 (0.84–0.90) | < 0.001 | 0.87 (0.84–0.90) | < 0.001 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.20 (1.16–1.23) | < 0.001 | 1.19 (1.16–1.23) | < 0.001 |
| BMI ≥ 28.0 kg/m 2 | 1.35 (1.28–1.43) | < 0.001 | 1.35 (1.27–1.42) | < 0.001 |
| Birth defects | ||||
| BMI < 18.5 kg/m2 | 0.98 (0.88–1.09) | 0.715 | 0.99 (0.89–1.36) | 0.973 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.06 (0.94–1.18) | 0.334 | 1.04 (0.93–1.17) | 0.513 |
| BMI ≥ 28.0 kg/m 2 | 1.09 (0.86–1.38) | 0.49 | 1.05 (0.83–1.34) | 0.666 |
| ABORTION | ||||
| BMI < 18.5 kg/m2 | 0.96 (0.76–1.20) | 0.717 | 0.99 (0.78–1.24) | 0.949 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.11 (0.89–1.38) | 0.363 | 1.02 (0.87–1.34) | 0.514 |
| BMI ≥ 28.0 kg/m 2 | 1.42 (1.95–2.13) | 0.087 | 1.40 (0.93–2.10) | 0.103 |
| Still birth | ||||
| BMI < 18.5 kg/m2 | 0.76 (0.59–0.97) | 0.028 | 0.82 (0.65–1.05) | 0.119 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.13 (0.92–1.39) | 0.025 | 1.07 (0.86–1.33) | 0.536 |
| BMI ≥ 28.0 kg/m 2 | 1.27 (0.85–1.92) | 0.247 | 1.20 (0.79–1.81) | 0.38 |
| Post-term pregnancy | ||||
| BMI < 18.5 kg/m2 | 0.80 (0.67–0.96) | 0.019 | 0.76 (0.63–0.92) | 0.005 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.37 (1.17–1.59) | < 0.001 | 1.39 (1.19–1.63) | 0.006 |
| BMI ≥ 28.0 kg/m 2 | 1.61 (1.21–2.15) | 0.001 | 1.66 (1.25–2.21) | < 0.001 |
| Caesarean-section | ||||
| BMI < 18.5 kg/m2 | 0.83 (0.79–0.87) | < 0.001 | 0.81 (0.76–0.84) | < 0.001 |
| 18.5 kg/m2 ≤ BMI < 24.0 kg/m 2 | 1 | 1 | ||
| 24.0 kg/m 2 ≤ BMI < 28.0 kg/m 2 | 1.70 (1.63–1.77) | < 0.001 | 1.60 (1.52–1.67) | < 0.001 |
| BMI ≥ 28.0 kg/m 2 | 2.09 (2.00–2.19) | < 0.001 | 2.05 (1.95–2.14) | < 0.001 |
**Pre-pregnancy BMI was adjusted for maternal age, ethnic group, education, area of residence, occupation, smoking, passive smoking, alcohol drinking, and sex of children.