Table 1.
Baseline characteristics of pregnancy according to the quartiles of dietary protein intake a (n(%)).
| Characteristic | Total (n = 1071) | Protein Intake Quartiles | p-Value b | |||
|---|---|---|---|---|---|---|
| Q1 (n = 268) | Q2 (n = 267) | Q3 (n = 269) | Q4 (n = 267) | |||
| Age (years) | 30.90 ± 3.93 | 30.37 ± 4.06 | 30.99 ± 3.63 | 31.06 ± 4.00 | 31.16 ± 4.02 | 0.086 |
| Pre-pregnancy BMI | 22.42 ± 3.82 | 22.85 ± 3.79 | 22.25 ± 3.69 | 22.13 ± 3.57 | 22.46 ± 4.18 | 0.140 |
| Ethnicity | 0.369 | |||||
| Han | 1052 (98.2) | 260 (97.0) | 264 (98.9) | 265 (98.5) | 263 (98.5) | |
| Other | 19 (1.8) | 8 (3.0) | 3 (1.1) | 4 (1.5) | 4 (1.5) | |
| Marital Status | 0.193 | |||||
| Married | 1059 (98.9) | 264 (98.5) | 267 (100.0) | 266 (98.9) | 262 (98.1) | |
| Unmarried or other | 12 (1.1) | 4 (1.5) | 0 (0.0) | 3 (1.1) | 5 (1.9) | |
| Annual household income (CNY) | 0.190 | |||||
| <50,000 | 159 (14.9) | 50 (18.7) | 33 (12.4) | 37 (13.8) | 39 (14.6) | |
| 50,000~99,900 | 369 (34.5) | 99 (37.1) | 96 (36.0) | 81 (30.1) | 93 (34.8) | |
| 100,000~199,900 | 387 (36.2) | 90 (33.7) | 93 (34.8) | 107 (39.8) | 97 (36.3) | |
| ≥200,000 | 155 (14.5) | 28 (10.5) | 45 (16.9) | 44 (16.4) | 38 (14.2) | |
| Education status | 0.826 | |||||
| Middle school and below | 176 (16.4) | 50 (18.7) | 46 (17.2) | 42 (15.6) | 38 (14.2) | |
| High school or technical secondary college | 223 (20.8) | 58 (21.6) | 52 (19.5) | 58 (21.6) | 55 (20.6) | |
| Junior college or regular college | 672 (62.7) | 160 (59.7) | 169 (63.3) | 169 (62.8) | 174 (65.2) | |
| Working Status | 0.296 | |||||
| Brain-based work | 585 (54.6) | 134 (50.0) | 159 (59.6) | 144 (53.5) | 148 (55.4) | |
| Physical-based work | 69 (6.4) | 18 (6.7) | 13 (4.9) | 16 (5.9) | 22 (8.2) | |
| Currently not working | 417 (38.9) | 116 (43.3) | 95 (35.6) | 109 (40.5) | 97 (36.3) | |
| Smoking | 0.266 | |||||
| Yes | 40 (3.7) | 14 (5.2) | 7 (2.6) | 7 (2.6) | 12 (4.5) | |
| No | 1031 (96.3) | 254 (94.8) | 260 (97.4) | 262 (97.4) | 255 (95.5) | |
| Drinking | 0.024 | |||||
| Yes | 172 (16.1) | 58 (21.6) | 42 (15.7) | 39 (14.5) | 33 (12.4) | |
| No | 899 (83.9) | 210 (78.4) | 225 (84.3) | 230 (85.5) | 234 (87.6) | |
| Age of menarche (years) | 0.801 | |||||
| 8~11 | 33 (3.1) | 7 (2.6) | 13 (4.9) | 8 (3.0) | 5 (1.9) | |
| 12 | 207 (19.3) | 58 (21.6) | 48 (18.0) | 53 (19.7) | 48 (18.0) | |
| 13 | 289 (27.0) | 68 (25.4) | 76 (28.5) | 68 (25.3) | 77 (28.8) | |
| 14 | 257 (24.0) | 64 (23.9) | 64 (24.0) | 62 (23.0) | 67 (25.1) | |
| ≥15 | 285 (26.6) | 71 (26.5) | 66 (24.7) | 78 (29.0) | 70 (26.2) | |
| Conception Season | <0.001 | |||||
| Spring | 287 (26.8) | 92 (34.3) | 84 (31.5) | 71 (26.4) | 40 (15.0) | |
| Autumn | 166 (15.5) | 53 (19.8) | 50 (18.7) | 41 (15.2) | 22 (8.2) | |
| Summer | 154 (14.4) | 30 (11.2) | 31 (11.6) | 34 (12.6) | 59 (22.1) | |
| Winter | 464 (43.3) | 93 (34.7) | 102 (38.2) | 123 (45.7) | 146 (54.7) | |
| Adverse maternal history | 0.069 | |||||
| No | 922 (86.1) | 242 (90.3) | 230 (86.1) | 230 (85.5) | 220 (82.4) | |
| Yes | 149 (13.9) | 26 (9.7) | 37 (13.9) | 39 (14.5) | 47 (17.6) | |
| Family history of diabetes | 0.236 | |||||
| No | 792 (73.9) | 195 (72.8) | 209 (78.3) | 192 (71.4) | 196 (73.4) | |
| Yes | 228 (21.3) | 56 (20.9) | 50 (18.7) | 60 (22.3) | 62 (23.2) | |
| Unclear | 51 (4.8) | 17 (6.3) | 8 (3.0) | 17 (6.3) | 9 (3.4) | |
| Family history of cardiovascular disease | 0.656 | |||||
| No | 833 (77.8) | 209 (78.0) | 201 (75.3) | 218 (81.0) | 205 (76.8) | |
| Yes | 175 (16.3) | 41 (15.3) | 50 (18.7) | 36 (13.4) | 48 (18.0) | |
| Unclear | 63 (5.9) | 18 (6.7) | 16 (6.0) | 15 (5.6) | 14 (5.2) | |
| Physical activity | 0.007 | |||||
| Low | 211 (19.7) | 52 (19.4) | 59 (22.1) | 52 (19.3) | 48 (18.0) | |
| Medium | 562 (52.5) | 119 (44.4) | 146 (54.7) | 140 (52.0) | 157 (58.8) | |
| High | 298 (27.8) | 97 (36.2) | 62 (23.2) | 77 (28.6) | 62 (23.2) | |
| Sleep quality | 0.141 | |||||
| Excellent | 19 (1.8) | 2 (0.7) | 6 (2.2) | 6 (2.2) | 5 (1.9) | |
| Good | 129 (12.0) | 34 (12.7) | 37 (13.9) | 38 (14.1) | 20 (7.5) | |
| Average | 923 (86.2) | 232 (86.6) | 224 (83.6) | 225 (83.6) | 242 (90.6) | |
a Continuous variables are presented as the mean ± SD; categorical variables are presented as the n (%). BMI, body mass index. b p-values are from ANOVA for continuous data and from chi-square tests for categorical data.