Table 3.
Analysis of selected pregnancy outcomes stratified by BMI
| Characteristics | PTB | Fetal distress | Neonatal asphyxia | ||||||
|---|---|---|---|---|---|---|---|---|---|
| No. of Studies | Pooled OR (95% CI) | P-value | No. of Studies | Pooled OR (95% CI) | P-value | No. of Studies | Pooled OR (95% CI) | P-value | |
| Underweight | |||||||||
| Sample size | |||||||||
| ≤ 10,000 | 13 | 0.92 (0.72–1.16) | 0.344 | 4 | 1.05 (0.80–1.13) | 0.505 | 9 | 1.24 (0.92–1.67) | – |
| 10,000~50,000 | 6 | 1.10 (0.99–1.22) | 1 | 0.93 (0.77–1.12) | 0 | NA | |||
| ≥ 50,000 | 2 | 1.06 (1.00–1.12) | 0 | NA | 0 | NA | |||
| BMI cut-off | |||||||||
| WHO | 4 | 1.17 (0.99–1.38) | 0.240 | 1 | 1.40 (0.60–3.30) | 0.445 | 1 | 1.57 (0.62–3.97) | 0.956 |
| APS | 1 | 1.05 (0.68–1.62) | 0 | NA | 1 | 0.90 (0.41–1.97) | |||
| WGOC | 16 | 0.99 (0.91–1.09) | 4 | 0.95 (0.81–1.12) | 7 | 1.26 (0.87–1.84) | |||
| BMI source | |||||||||
| Recorded | 10 | 1.00 (0.82–1.20) | 0.775 | 3 | 1.03 (0.78–1.38) | 0.674 | 7 | 1.30 (0.90–1.88) | 0.569 |
| Measured | 4 | 1.05 (0.91–1.22) | 0 | NA | 0 | NA | |||
| Self-reported | 4 | 0.92 (0.68–1.24) | 1 | 0.93 (0.77–1.12) | 0 | NA | |||
| Questionnaire | 2 | 1.20 (1.03–1.39) | 1 | 1.52 (0.43–5.31) | 1 | 1.81 (0.60–5.48) | |||
| Not reported | 1 | 0.94 (0.69–1.27) | 0 | NA | 1 | 0.91 (0.54–1.54) | |||
| Language | |||||||||
| English | 10 | 1.03 (0.95–1.12) | 0.688 | 2 | 0.93 (0.78–1.10) | 0.388 | 0 | NA | – |
| Chinese | 11 | 1.04 (0.84–1.29) | 3 | 1.14 (0.79–1.64) | 9 | 1.24 (0.92–1.67) | |||
| Confounders | |||||||||
| Adjusted | 12 | 1.01 (0.93–1.10) | 0.276 | 2 | 0.93 (0.78–1.10) | 0.388 | 0 | NA | – |
| Unadjusted | 9 | 1.12 (0.89–1.40) | 3 | 1.14 (0.79–1.64) | 9 | 1.24 (0.92–1.67) | |||
| Geographic region | |||||||||
| North China | 8 | 0.79 (0.62–1.01) | 0.083 | 2 | 0.99 (0.65–1.50) | 0.901 | 2 | 1.14 (0.59–2.20) | 0.875 |
| South China | 10 | 1.13 (0.98–1.30) | 3 | 0.96 (0.81–1.14) | 7 | 1.25 (0.87–1.81) | |||
| All | 3 | 1.06 (1.01–1.12) | 0 | NA | 0 | NA | |||
| Overweight/Obesity | |||||||||
| Sample size | |||||||||
| ≤ 10,000 | 13 | 1.64 (1.46–1.83) | < 0.001 | 4 | 0.94 (0.50–1.77) | 0.869 | 9 | 1.74 (1.38–2.18) | – |
| 10,000~50,000 | 6 | 1.28 (1.13–1.45) | 1 | 0.85 (0.60–1.19) | 0 | NA | |||
| ≥ 50,000 | 2 | 1.10 (1.05–1.15) | 0 | NA | 0 | NA | |||
| BMI cut-off | |||||||||
| WHO | 4 | 1.40 (1.14–1.79) | 0.775 | 1 | 0.92 (0.44–1.92) | 0.997 | 1 | 1.08 (0.49–2.39) | 0.227 |
| APS | 1 | 1.39 (0.78–2.49) | 0 | NA | 1 | 1.42 (0.54–3.71) | |||
| WGOC | 16 | 1.37 (1.23–1.54) | 4 | 0.91 (0.54–1.52) | 7 | 1.84 (1.44–2.34) | |||
| BMI source | |||||||||
| Recorded | 10 | 1.29 (1.14–1.47) | 0.245 | 3 | 0.65 (0.49–0.86) | 0.097 | 7 | 1.72 (1.32–2.24) | 0.830 |
| Measured | 4 | 1.24 (0.99–1.56) | 0 | NA | 0 | NA | |||
| Self-reported | 4 | 1.79 (1.44–2.24) | 1 | 0.85 (0.60–1.19) | 0 | NA | |||
| Questionnaire | 2 | 1.42 (0.93–2.19) | 1 | 2.63 (1.37–5.03) | 1 | 2.76 (1.50–5.08) | |||
| Not reported | 1 | 1.42 (1.01–1.99) | 0 | NA | 1 | 1.11 (0.60–2.07) | |||
| Language | |||||||||
| English | 10 | 1.39 (1.23–1.56) | 0.839 | 2 | 0.74 (0.56–0.98) | 0.533 | 0 | NA | – |
| Chinese | 11 | 1.37 (1.18–1.60) | 3 | 1.10 (0.44–2.79) | 9 | 1.74 (1.38–2.18) | |||
| Confounders | |||||||||
| Adjusted | 12 | 1.38 (1.23–1.55) | 0.983 | 2 | 0.74 (0.56–0.98) | 0.533 | 0 | NA | – |
| Unadjusted | 9 | 1.46 (1.29–1.52) | 3 | 1.10 (0.44–2.79) | 9 | 1.74 (1.38–2.18) | |||
| Geographic region | |||||||||
| North China | 8 | 1.63 (1.41–1.88) | 0.002 | 2 | 1.26 (0.31–5.07) | 0.472 | 2 | 2.21 (1.19–4.09) | 0.283 |
| South China | 10 | 1.26 (1.12–1.41) | 3 | 0.77 (0.59–1.01) | 7 | 1.63 (1.26–2.09) | |||
| All | 3 | 1.11 (1.06–1.16) | 0 | NA | 0 | NA | |||
NA not available, BMI body mass index, WHO World Health Organization, APS Asia-Pacific standard, WGOC Working Group on Obesity in China, LGA large for gestational age, SGA small for gestational age, LBW low birth weight, PTB premature birth