Table 2.
Characteristics of participants with SGA and AGA among primiparae in Wuhan, China (n=8737)
| Variables | n(%) or Mean±SD | SGA | AGA | P values |
| n(%) or Mean±SD | n(%) or Mean±SD | |||
| GWG by IOM recommendations | ||||
| Below | 901 (10.31) | 208 (22.44) | 693 (8.87) | <0.001 |
| Within and above | 7836 (89.69) | 719 (77.56) | 7117 (91.13) | |
| Prepregnancy BMI | ||||
| <18.5 | 2082 (23.83) | 309 (33.33) | 1773 (22.70) | <0.001 |
| ≥18.5 | 6655 (76.17) | 618 (66.67) | 6037 (77.30) | |
| Physical activity during the last trimester of pregnancy | ||||
| Almost none per week | 834 (9.55) | 79 (8.52) | 755 (9.67) | 0.495 |
| 1–2 days per week | 831 (9.51) | 86 (9.28) | 745 (9.54) | |
| 3–4 days per week | 663 (7.59) | 61 (6.58) | 602 (7.71) | |
| 5–6 days per week | 146 (1.67) | 17 (1.83) | 129 (1.65) | |
| Every day per week | 6263 (71.68) | 684 (73.79) | 5579 (71.43) | |
| Sleep quality in the month before the birth | ||||
| Bad | 3063 (35.06) | 310 (33.44) | 2753 (35.25) | 0.275 |
| Good | 5674 (64.94) | 617 (66.56) | 5057 (64.75) | |
| A multivitamin supplement during the first trimester of pregnancy | ||||
| No | 3640 (41.66) | 434 (46.82) | 3206 (41.05) | 0.001 |
| Yes | 5097 (58.34) | 493 (53.18) | 4604 (58.95) | |
| Infant’s gender | ||||
| Boy | 4499 (51.49) | 467 (50.38) | 4032 (51.63) | 0.517 |
| Girl | 4238 (48.51) | 460 (49.62) | 3778 (48.37) | |
| Passive smoking during pregnancy | ||||
| No | 7717 (88.33) | 813 (87.7) | 6904 (88.40) | 0.532 |
| Yes | 1020 (11.67) | 114 (12.3) | 906 (11.60) | |
| Maternal age | 27.70±3.24 | 27.32±3.50 | 27.75±3.21 | <0.001 |
| PIH | ||||
| No | 8468 (96.92) | 882 (95.15) | 7586 (97.13) | 0.001 |
| Yes | 269 (3.08) | 45 (4.85) | 224 (2.87) | |
| SES | ||||
| Low | 2933 (33.60) | 361 (38.94) | 2572 (32.93) | <0.001 |
| High | 5804 (66.40) | 566 (61.06) | 5238 (67.07) | |
AGA, appropriate-for-gestational-age; BMI, body mass index; GWG, gestational weight gain; IOM, Institute of Medicine; PIH, pregnancy-induced hypertension syndrome; SES, socioeconomic status; SGA, small-for-gestational-age.