Table 1. Characteristics of pregnant women between groups of GDM and non-GDM in Beijing, China, 2017–2021, n (%).
| Variable | Total* | Non-GDM* | GDM* | P value † |
| Abbreviation: GDM=gestational diabetes mellitus; BMI=body mass index. * The total value differs from the sum of subgroups due to the exclusion of cases with missing data. † Differences in prevalence of GDM by subcategory were examined with the Chi-square test. § Smoking included exposure to passive smoking. | ||||
| Total | 3,421 (100.0) | 2,778 (81.2) | 643 (18.8) | |
| Age (years) | <0.001 | |||
| <30 | 1,675 (49.0) | 1,411 (84.2) | 264 (15.8) | |
| ≥30 | 1,746 (51.0) | 1,367 (78.3) | 379 (21.7) | |
| Pre-pregnancy BMI (kg/m2) | <0.001 | |||
| <24 | 2,654 (81.6) | 2,219 (83.6) | 435 (16.4) | |
| ≥24 | 598 (18.4) | 414 (69.2) | 184 (30.8) | |
| Occupation | 0.072 | |||
| None | 219 (6.5) | 168 (76.7) | 51 (23.3) | |
| Teacher/doctor/technician | 1,109 (32.8) | 927 (83.6) | 182 (16.4) | |
| Business/service | 791 (23.4) | 642 (81.2) | 149 (18.8) | |
| Public official | 698 (20.7) | 554 (79.4) | 144 (20.6) | |
| Others | 562 (16.6) | 458 (81.5) | 104 (18.5) | |
| Education | 0.031 | |||
| Master or above | 957 (27.7) | 795 (83.9) | 152 (16.1) | |
| College or university | 2,247 (65.1) | 1,790 (80.4) | 436 (19.6) | |
| High school or below | 250 (7.2) | 191 (78.3) | 53 (21.7) | |
| Ethnicity | 0.875 | |||
| Han | 3,208 (93.8) | 2,629 (81.1) | 613 (18.9) | |
| Others | 211 (6.2) | 175 (81.8) | 39 (18.2) | |
| Smoking | 0.003 | |||
| No | 2,574 (76.0) | 2,120 (82.4) | 454 (17.6) | |
| Yes§ | 813 (24.0) | 631 (77.3) | 182 (22.7) | |
| Parity | 0.014 | |||
| Nulliparous | 2,464 (80.6) | 2,020 (82.0) | 444 (18.0) | |
| Multiparous | 593 (19.4) | 460 (77.6) | 134 (22.4) | |
| Food consumption | ||||
| Meat (times/week) | 0.198 | |||
| ≤3 | 1,965 (59.8) | 1,610 (81.9) | 365 (18.1) | |
| 4–6 | 727 (22.1) | 588 (80.9) | 139 (19.1) | |
| >6 | 595 (18.1) | 468 (78.7) | 127 (21.3) | |
| Egg (times/week) | 0.026 | |||
| ≤3 | 1,094 (32.2) | 913 (83.5) | 181 (16.5) | |
| 4–6 | 1,116 (33.8) | 903 (80.9) | 213 (19.1) | |
| >6 | 1,087 (33.0) | 858 (78.9) | 229 (21.1) | |
| Milk (times/week) | 0.015 | |||
| ≤3 | 1,253 (38.0) | 1,048 (83.6) | 205 (16.4) | |
| 4–6 | 995 (30.2) | 788 (79.2) | 207 (20.8) | |
| >6 | 1,046 (31.8) | 837 (80.0) | 209 (20.0) | |
| Vegetable (times/week) | 0.138 | |||
| ≤3 | 326 (9.9) | 274 (84.0) | 52 (16.0) | |
| 4–6 | 809 (24.6) | 668 (82.6) | 141 (17.4) | |
| >6 | 2,159 (65.5) | 1,733 (80.3) | 426 (19.7) | |
| Fruit (times/week) | 0.554 | |||
| ≤3 | 173 (5.2) | 146 (84.4) | 27 (15.6) | |
| 4–6 | 637 (19.3) | 518 (81.3) | 119 (18.7) | |
| >6 | 2,492 (75.5) | 2,020 (81.1) | 472 (18.9) | |
| Soybean (times/week) | 0.652 | |||
| ≤3 | 1,898 (57.9) | 1,553 (81.8) | 345 (18.2) | |
| 4–6 | 865 (26.4) | 698 (80.7) | 167 (19.3) | |
| >6 | 514 (15.7) | 413 (80.4) | 101 (19.6) | |