Table 3.
Adjusted risk ratios (RR) and 95% confidence intervals (CI) for associations between prenatal risk factors and intrauterine growth abnormalities.
| Risk factors during pregnancy | SGA (n = 35,069) RR (95% CI) |
LGA (n = 160,253) RR (95% CI) |
|---|---|---|
| Pre-pregnancy BMI (kg) | ||
| < 18.5 (low body weight) | 1.68 (1.62, 1.74) | 0.48 (0.46, 0.50) |
| 18.5–23.9 (normal body weight) | 1.00 | 1.00 |
| 24-27.9 (overweight) | 0.78 (0.75, 0.80) | 1.68 (1.66, 1.71) |
| 28 (obese) | 0.81 (0.77, 0.85) | 2.36 (2.31, 2.40) |
| GWG (Chinese Standard) | ||
| Insufficient weight gain | 1.40 (1.29, 1.51) | 0.80 (0.75, 0.84) |
| Proper weight gain | 1.00 | 1.00 |
| Excessive weight gain | 0.65 (0.62, 0.68) | 1.78 (1.73, 1.83) |
| HDP | ||
| Health | 1.00 | 1.00 |
| Pregnancy complicated with chronic hypertension | 1.34 (1.24, 1.44) | 1.34 (1.29, 1.39) |
| CH Concurrent preeclampsia | 1.79 (1.51, 2.13) | 1.47 (1.33, 1.62) |
| Hypertension of pregnancy | 1.53 (1.45, 1.62) | 1.23 (1.19, 1.27) |
| Preeclampsia | 2.07 (1.87, 2.30) | 1.31 (1.23, 1.41) |
| Fasting blood glucose in early pregnancy | ||
| Glucopenia | 1.16 (1.10, 1.22) | 0.92 (0.90, 0.95) |
| Euglycemia | 1.00 | 1.00 |
| Hyperglycaemia | 0.96 (0.93, 0.99) | 1.34 (1.32, 1.36) |
| Early pregnancy fasting urine sugar | ||
| The urine sugar is normal | 1.00 | 1.00 |
| Urine sugar is high | 1.06 (0.93, 1.21) | 1.51 (1.42, 1.60) |
| Hemoglobin in early pregnancy | ||
| Hemoglobin is too low | 1.01 (0.97, 1.06) | 0.94 (0.92, 0.97) |
| Hemoglobin was normal | 1.00 | 1.00 |
| Folate supplementation in early pregnancy | ||
| Yes | 1.00 | 1.00 |
| Deny | 0.99 (0.97, 1.02) | 0.98 (0.97, 0.99) |
| Assisted reproduction | ||
| Yes | 1.41 (1.17, 1.69) | 0.92 (0.82, 1.02) |
| Deny | 1.00 | 1.00 |
| Exposure of teratogens | ||
| Yes | 1.07 (0.99, 1.16) | 0.98 (0.94, 1.03) |
| Deny | 1.00 | 1.00 |
SGA small-for-gestational-age, LGA large-for-gestational-age.