Table 2.
Analysis of infant birth weight stratified by BMI
| Characteristics | LBW | SGA | Macrosomia | LGA | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 | No. of Studies | Pooled OR (95% CI) | P-value | |
| Underweight | ||||||||||||
| Sample size | ||||||||||||
| ≤ 10,000 | 8 | 2.22 (1.10–4.52) | 0.187 | 6 | 2.03 (1.37–3.00) | 0.394 | 20 | 0.46 (0.38–0.55) | 0.350 | 4 | 0.55 (0.46–0.67) | 0.367 |
| 10,000~50,000 | 5 | 1.37 (1.13–1.65) | 3 | 1.78 (1.61–1.97) | 6 | 0.52 (0.41–0.66) | 3 | 0.44 (0.31–0.62) | ||||
| ≥ 50,000 | 2 | 1.28 (1.14–1.43) | 1 | 1.46 (1.37–1.55) | 1 | 0.56 (0.51–0.61) | 0 | NA | ||||
| BMI cut-off | ||||||||||||
| WHO | 1 | 3.52 (1.66–7.49) | 0.233 | 2 | 1.85 (0.64–2.07) | 0.841 | 4 | 0.41 (0.25–0.67) | 0.843 | 1 | 0.32 (0.25–0.41) | 0.073 |
| APS | 3 | 2.14 (0.59–7.72) | 0 | NA | 3 | 0.60 (0.34–1.07) | 0 | NA | ||||
| WGOC | 11 | 1.43 (1.24–1.64) | 8 | 1.74 (1.46–2.06) | 20 | 0.49 (0.44–0.55) | 6 | 0.52 (0.44–0.62) | ||||
| BMI source | ||||||||||||
| Recorded | 11 | 1.72 (1.39–2.14) | 0.239 | 4 | 1.88 (1.47–2.41) | 0.698 | 18 | 0.51 (0.43–0.60) | 0.332 | 3 | 0.50 (0.37–0.67) | 0.225 |
| Measured | 1 | 1.30 (0.97–1.73) | 2 | 1.53 (1.28–1.83) | 1 | 0.54 (0.45–0.63) | 2 | 0.59 (0.53–0.66) | ||||
| Self-reported | 0 | NA | 1 | 2.28 (0.75–6.92) | 3 | 0.48 (0.39–0.58) | 0 | NA | ||||
| Questionnaire | 1 | 1.64 (0.96–2.80) | 3 | 1.73 (1.21–2.48) | 2 | 0.52 (0.30–0.88) | 2 | 0.38 (0.26–0.55) | ||||
| Not reported | 2 | 0.88 (0.34–2.23) | 0 | NA | 3 | 0.37 (0.23–0.60) | 0 | NA | ||||
| Language | ||||||||||||
| English | 3 | 1.31 (1.18–1.44) | 0.486 | 5 | 1.70 (1.46–1.99) | 0.717 | 5 | 0.50 (0.44–0.57) | 0.975 | 3 | 0.39 (0.32–0.49) | 0.009 |
| Chinese | 12 | 1.81 (1.31–2.50) | 5 | 1.75 (1.52–2.02) | 22 | 0.48 (0.41–0.58) | 4 | 0.59 (0.53–0.65) | ||||
| Confounders | ||||||||||||
| Adjusted | 5 | 1.24 (1.13–1.37) | 0.307 | 8 | 1.63 (1.44–1.85) | 0.022 | 7 | 0.56 (0.47–0.68) | 0.127 | 6 | 0.48 (0.38–0.61) | 0.967 |
| Unadjusted | 10 | 1.95 (1.38–2.75) | 2 | 3.66 (1.46–9.16) | 20 | 0.45 (0.38–0.53) | 1 | 0.48 (0.32–0.72) | ||||
| Geographic region | ||||||||||||
| North China | 6 | 1.31 (0.94–1.83) | 0.510 | 4 | 1.82 (1.67–2.00) | 0.914 | 12 | 0.45 (0.41–0.49) | 0.212 | 3 | 0.43 (0.37–0.50) | 0.764 |
| South China | 7 | 2.08 (1.41–3.05) | 6 | 1.77 (1.43–2.20) | 14 | 0.50 (0.40–0.63) | 4 | 0.49 (0.36–0.68) | ||||
| All | 2 | 1.52 (1.19–1.94) | 0 | NA | 1 | 0.59 (0.51–0.67) | 0 | NA | ||||
| Overweight/Obesity | ||||||||||||
| Sample size | ||||||||||||
| ≤ 10,000 | 8 | 1.24 (0.90–1.71) | 0.718 | 6 | 1.21 (0.84–1.73) | 0.135 | 20 | 2.05 (1.75–2.40) | 0.284 | 4 | 1.67 (1.40–1.98) | 0.162 |
| 10,000~50,000 | 5 | 1.04 (0.81–1.34) | 3 | 0.69 (0.64–0.75) | 6 | 1.75 (1.52–2.01) | 3 | 2.06 (1.76–2.41) | ||||
| ≥ 50,000 | 2 | 1.32 (1.04–1.68) | 1 | 0.84 (0.75–0.94) | 1 | 1.83 (1.68–1.99) | 0 | NA | ||||
| BMI cut-off | ||||||||||||
| WHO | 1 | 1.34 (0.54–3.33) | 0.731 | 2 | 1.29 (0.31–5.38) | 0.733 | 4 | 1.90 (1.19–3.04) | 0.776 | 1 | 2.41 (2.19–2.64) | 0.067 |
| APS | 3 | 1.19 (0.79–1.80) | 0 | NA | 3 | 1.90 (1.13–3.18) | 0 | NA | ||||
| WGOC | 10 | 1.15 (0.97–1.36) | 8 | 0.89 (0.74–1.05) | 20 | 1.92 (1.76–2.10) | 6 | 1.79 (1.58–2.02) | ||||
| BMI source | ||||||||||||
| Recorded | 11 | 1.19 (1.05–1.35) | 0.621 | 4 | 0.77 (0.69–0.86) | 0.392 | 18 | 2.03 (1.82–2.27) | 0.446 | 3 | 1.66 (1.28–2.16) | 0.097 |
| Measured | 1 | 0.35 (0.14–0.85) | 2 | 0.99 (0.54–1.82) | 1 | 1.89 (1.57–2.30) | 2 | 1.78 (1.56–2.03) | ||||
| Self-reported | 0 | NA | 1 | 2.82 (1.29–6.17) | 3 | 1.28 (0.95–1.71) | 0 | NA | ||||
| Questionnaire | 1 | 2.08 (1.31–3.32) | 3 | 0.97 (0.54–1.73) | 2 | 1.90 (1.30–2.78) | 2 | 2.38 (2.18–2.60) | ||||
| Not reported | 2 | 0.92 (0.44–1.93) | 0 | NA | 3 | 2.13 (1.72–2.65) | 0 | NA | ||||
| Language | ||||||||||||
| English | 3 | 1.28 (1.09–1.50) | 0.367 | 5 | 0.77 (0.65–0.91) | 0.167 | 5 | 1.57 (1.33–1.85) | 0.028 | 3 | 2.02 (1.69–2.42) | 0.329 |
| Chinese | 12 | 1.06 (0.83–1.36) | 5 | 1.12 (0.85–1.47) | 22 | 2.06 (1.84–2.31) | 4 | 1.74 (1.51–2.01) | ||||
| Confounders | ||||||||||||
| Adjusted | 5 | 1.34 (1.08–1.65) | 0.064 | 8 | 0.88 (0.73–1.05) | 0.824 | 7 | 1.60 (1.37–1.88) | 0.026 | 6 | 1.86 (1.61–2.15) | 0.714 |
| Unadjusted | 10 | 1.09 (1.00–1.20) | 2 | 1.02 (0.60–1.76) | 20 | 2.08 (1.86–2.33) | 1 | 2.05 (1.45–2.89) | ||||
| Geographic region | ||||||||||||
| North China | 6 | 1.16 (0.99–1.35) | 0.805 | 4 | 1.04 (0.68–1.57) | 0.584 | 12 | 1.69 (1.49–1.92) | 0.041 | 3 | 1.85 (1.58–2.16) | 0.807 |
| South China | 7 | 1.28 (0.98–1.66) | 6 | 0.84 (0.67–1.04) | 14 | 2.18 (1.87–2.55) | 4 | 1.88 (1.45–2.42) | ||||
| All | 2 | 1.04 (0.80–1.35) | 0 | NA | 1 | 2.18 (2.02–2.36) | 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