Pregnancy characteristics of AGA group and SGA group matched according to 1:4 PSM analysis
| Variables | Items | AGA group (n=1528） | SGA group (n=382） | x2/t | P value |
| Parity | Nulliparous | 539 (35.3) | 195 (51) | 32.13 | <0.001 |
| Multiparous | 989 (64.7) | 187 (49) | |||
| Assisted reproductive technology | No | 1446 (94.6) | 362 (94.8) | 0.01 | 0.919 |
| Yes | 82 (5.4) | 20 (5.2) | |||
| Previous uterine scar | No | 1196 (78.3) | 337 (88.2) | 19.089 | <0.001 |
| Yes | 332 (21.7) | 45 (11.8) | |||
| Family history | No | 1367 (89.5) | 336 (88) | 2.809 | 0.422 |
| Hypertension | 76 (5) | 26 (6.8) | |||
| Diabetes | 46(3) | 13 (3.4) | |||
| Both | 39 (2.6) | 7 (1.8) | |||
| History of abortion or miscarriage | No | 896 (58.6) | 251 (65.7) | 6.393 | 0.041 |
| Spontaneous miscarriage | 348 (22.8) | 71 (18.6) | |||
| Induced abortions | 284 (18.6) | 60 (15.7) | |||
| History of preterm delivery | No | 1467 (96) | 368 (96.3) | 0.087 | 0.768 |
| Yes | 61 (4) | 14 (3.7) | |||
| History of macrosomia | No | 1481 (96.9) | 379 (99.2) | 6.29 | 0.012 |
| Yes | 47 (3.1) | 3 (0.8) | |||
| History of GDM | No | 1523 (99.7) | 382 (100) | / | 0.590b |
| Yes | 5 (0.3) | 0 (0) | |||
| History of fetal distress | No | 1512 (99) | 380 (99.5) | 0.897 | 0.343 |
| Yes | 16 (1) | 2 (0.5) | |||
| History of low birth weight | No | 1523 (99.7) | 376 (98.4) | / | 0.011b |
| Yes | 5 (0.3) | 6 (1.6) | |||
| Intrahepatic cholestasis of pregnancy | No | 1508 (98.7) | 377 (98.7) | 0 | 1 |
| Yes | 20 (1.3) | 5 (1.3) | |||
| Gestational hypertensive disorder | No | 1431 (93.7) | 324 (84.8) | 31.269 | <0.001b |
| Gestational hypertension | 62 (4.1) | 31 (8.1) | |||
| Preeclampsia and eclampsia | 27 (1.8) | 22 (5.8) | |||
| Chronic hypertension with superimposed preeclampsia | 4 (0.3) | 3 (0.8) | |||
| Chronic hypertension (of any cause) | 4 (0.3) | 2 (0.5) | |||
| Hyperthyroid | No | 1487 (97.3) | 376 (98.4) | 1.576 | 0.209 |
| Yes | 41 (2.7) | 6 (1.6) | |||
| Hypothyroid | No | 1434 (93.8) | 349 (91.4) | 3.045 | 0.081 |
| Yes | 94 (6.2) | 33 (8.6) | |||
| Anaemia | No | 1149 (75.2) | 307 (80.4) | 4.508 | 0.034 |
| Yes | 379 (24.8) | 75 (19.6) | |||
| Polyhydramnios | No | 1517 (99.3) | 381 (99.7) | / | 0.479b |
| Yes | 11 (0.7) | 1 (0.3) | |||
| Oligohydramnios | No | 1490 (97.5) | 349 (91.4) | 32.314 | <0.001 |
| Yes | 38 (2.5) | 33 (8.6) | |||
| Ketonuria in first trimester (mmol/L) | <0.5 | 1049 (68.7) | 275 (72) | 9.963 | 0.007 |
| 0.5–3.9 | 336 (22) | 59 (15.4) | |||
| ≥4 | 143 (9.4) | 48 (12.6) | |||
| Ketonuria in second trimester (mmol/L) | <0.5 | 1090 (71.3) | 293 (76.7) | 4.903 | 0.086 |
| 0.5–3.9 | 308 (20.2) | 59 (15.4) | |||
| ≥4 | 130 (8.5) | 30 (7.9) | |||
| Elevated blood glucose in OGTT | One item | 482 (31.5) | 161 (42.1) | 24.605 | <0.001 |
| Two items | 878 (57.5) | 204 (53.4) | |||
| Three items | 168 (11.0) | 17 (4.5) | |||
| 75 g OGTT 0-hour glycaemia (mmol/L) | 4.83±0.48 | 4.64±0.44 | 7.187 | <0.001 | |
| 75 g OGTT 1-hour glycaemia (mmol/L) | 9.84±1.41 | 9.89±1.36 | −0.585 | 0.559 | |
| 75 g OGTT 2-hour glycaemia (mmol/L) | 8.06±1.59 | 7.83±1.58 | 2.586 | 0.01 | |
| FPG in the second trimester (mmol/L) | 4.87±0.56 | 4.73±0.49 | 4.372 | <0.001 | |
| 2-hour postprandial glucose in second trimester (mmol/L) | 6.09±1.30 | 5.7±1.14 | 5.825 | <0.001 | |
| HbA1c in the second trimester (mmol/L) | 5.26±0.36 | 5.28±0.35 | −1.008 | 0.314 | |
Bold values were statistically significant. b Fisher exact test.
AGA, appropriate weight for gestational age; FPG, fasting plasma glucose; HbA1c, haemoglobin A1c; OGTT, oral glucose tolerance test; the first trimester of pregnancy, 7–10 gestational weeks; the second trimester of pregnancy, 21–24 gestational weeks; the third trimester of pregnancy, 33–37 gestational weeks; PSM, propensity score matching; SGA, small for gestational age.