Table 3.
ORs (95% CIs) for pregnancy outcomes by gestational diabetes mellitus, stratified by maternal age.
| Age < 35 years | Age ≥ 35 years | P for interaction | |||
|---|---|---|---|---|---|
| OR (95% CI) | P value | OR (95% CI) | P value | ||
| Cesarean delivery | |||||
| Model 1 | 1.75 (1.53, 2.01) | <0.001 | 1.27 (0.84, 1.91) | 0.255 | 0.042 |
| Model 2 | 1.71 (1.49, 1.97) | <0.001 | 1.13 (0.74, 1.73) | 0.559 | 0.025 |
| Preterm birth∗ | |||||
| Model 1 | 1.49 (1.19, 1.88) | <0.001 | 0.75 (0.40, 1.41) | 0.376 | 0.158 |
| Model 2 | 1.45 (1.15, 1.83) | 0.002 | 0.73 (0.38, 1.40) | 0.334 | 0.133 |
| Low birth weight | |||||
| Model 1 | 1.25 (0.92, 1.69) | 0.155 | 0.83 (0.37, 1.89) | 0.665 | 0.539 |
| Model 2 | 0.81 (0.54, 1.22) | 0.319 | 2.28 (0.55, 9.43) | 0.256 | 0.383 |
| SGA | |||||
| Model 1 | 0.81 (0.60, 1.10) | 0.176 | 0.63 (0.26, 1.51) | 0.298 | 0.532 |
| Model 2 | 0.80 (0.59, 1.08) | 0.143 | 0.63 (0.25, 1.58) | 0.322 | 0.463 |
| Macrosomia | |||||
| Model 1 | 1.49 (1.18, 1.90) | 0.001 | 1.58 (0.81, 3.08) | 0.178 | 0.830 |
| Model 2 | 1.65 (1.28, 2.11) | <0.001 | 1.52 (0.73, 3.16) | 0.265 | 0.954 |
| LGA | |||||
| Model 1 | 1.43 (1.17, 1.75) | <0.001 | 1.55 (0.89, 2.72) | 0.121 | 0.963 |
| Model 2 | 1.39 (1.13, 1.70) | <0.001 | 1.35 (0.75, 2.44) | 0.316 | 0.898 |
Abbreviations: CI: confidence interval; OR: odds ratio; SGA: small for gestational age; LGA: large for gestational age. Model 1 was adjusted for demographic characteristics including maternal age, education, employment, annual household income, and study centers. Model 2 was further adjusted for drinking during pregnancy, passive smoking during pregnancy, prepregnancy body mass index categories, parity, use of assisted reproductive technology, folic acid supplementation, gestational age at delivery, and gestational weight gain categories. Preterm birth was not adjusted for gestational age at delivery∗.