Table 1.
Characteristics of participants by gestational diabetes mellitus.
| All | GDM | Non-GDM | P value | |
|---|---|---|---|---|
| Participants, n (%) | 8844 | 1229 (13.9) | 7615 (86.1) | — |
| Maternal age (year), median (IQR) | 28 (26, 31) | 29 (26, 32) | 28 (26, 30) | <0.001 |
| Maternal age, n (%) | <0.001 | |||
| <35 years | 8095 (91.5) | 1074 (87.4) | 7021 (92.2) | |
| ≥35 years | 749 (8.5) | 155 (12.6) | 594 (7.8) | |
| Education, n (%) | 0.801 | |||
| High school and below | 3346 (37.8) | 461 (37.5) | 2885 (37.9) | |
| College or graduate school | 5498 (62.2) | 768 (62.5) | 4730 (62.1) | |
| Employment, n (%) | 0.304 | |||
| Unemployed | 6456 (73.0) | 912 (74.2) | 5544 (72.8) | |
| Employed | 2388 (27.0) | 317 (25.8) | 2071 (27.2) | |
| Annual household income (RMB), n (%) | 0.874 | |||
| <10000 | 7071 (80.0) | 980 (79.7) | 6091 (80.0) | |
| 10001-20000 | 1288 (14.6) | 184 (15.0) | 1104 (14.5) | |
| >20000 | 485 (5.4) | 65 (5.3) | 420 (5.5) | |
| Drinking during pregnancy, n (%) | 0.014 | |||
| No | 8607 (97.3) | 1209 (98.4) | 7398 (97.2) | |
| Yes | 237 (2.7) | 20 (1.6) | 217 (2.8) | |
| Passive smoking during pregnancy, n (%) | 0.014 | |||
| No | 7059 (79.8) | 949 (77.2) | 6110 (80.2) | |
| Yes | 1785 (20.2) | 280 (22.8) | 1505 (19.8) | |
| Prepregnancy BMI categories, n (%) | <0.001 | |||
| Underweight | 7732 (87.4) | 963 (78.4) | 6769 (88.9) | |
| Normal weight | 946 (10.7) | 204 (16.6) | 742 (9.7) | |
| Overweight/obesity | 166 (1.9) | 62 (5.0) | 104 (1.4) | |
| Parity, n (%) | 0.136 | |||
| Primiparous | 7237 (81.8) | 987 (80.3) | 6250 (82.1) | |
| Multiparous | 1607 (18.2) | 242 (19.7) | 1365 (17.9) | |
| Use of ART, n (%) | 0.020 | |||
| No | 8680 (98.2) | 1196 (97.3) | 7484 (98.3) | |
| Yes | 164 (1.8) | 33 (2.7) | 131 (1.7) | |
| Folic acid supplementation, n (%) | 0.237 | |||
| No | 4067 (46.0) | 546 (44.4) | 3521 (46.2) | |
| Yes | 4777 (54.0) | 683 (44.6) | 4094 (53.8) | |
| Gestational age at delivery (week), median (IQR) | 39 (38, 40) | 39 (38, 39) | 39 (38, 40) | <0.001 |
| Gestational weight gain (kg) | <0.001 | |||
| Lower | 1282 (14.5) | 245 (19.9) | 1037 (13.6) | |
| Middle | 6367 (72.0) | 833 (67.8) | 5534 (72.7) | |
| Higher | 1195 (13.5) | 151 (12.3) | 1044 (13.7) |
Abbreviations: ART: assisted reproductive technology; BMI: body mass index; GDM: gestational diabetes mellitus. Values are the median (interquartile range) or n (%).