Total ( n = 5584) | BW, g | ||||||
---|---|---|---|---|---|---|---|
< 1000 ( n = 314) | 1000 – 1499 ( n = 1186) | 1500 – 2499 ( n = 2433) | 2500 – 3999 ( n = 1535) | ≥ 4000 ( n = 116) | P -value | ||
Gestational age (week) | 33.4 ± 3.6 | 27.8 ± 1.9* | 30 ± 1.8* | 32.9 ± 1.8* | 37.5 ± 2.2 | 39.2 ± 1.6* | < 0.001 |
BW (g) | 2105 ± 840 | 859 ± 100* | 1274 ± 140* | 1941 ± 285* | 3088 ± 403 | 4365 ± 477* | < 0.001 |
Male, n (%) | 3347(59.9) | 175(56)* | 650(54.8)* | 1438(59.1)* | 999(64.9) | 85(73.3) | < 0.001 |
Cesarean delivery, n(%) | 3664(65.60) | 158(50.60)* | 711(59.90)* | 1688(69.30) | 1081(66.20) | 89(76.70) | < 0.001 |
Fetal distress, n(%) | 564(11.2) | 34(12.6) | 112(11.0)* | 206(9.2)* | 193(13.8) | 19(3.8) | < 0.001 |
Congenital anomalies, n(%) | 103(1.8%) | 11(3.5%) | 18(1.5%) | 39(1.6%) | 32(2%) | 3(2.5%) | 0.127 |
Antenatal steroid usea, n(%) | 1594(33.2) | 126(46.8)* | 519(51.0)* | 830(39.5)* | 117(8.9) | 2(2.0)* | < 0.001 |
Gestational diabetes, n(%) | 907(16.2) | 39(12.5) | 205(17.2) | 381(15.6) | 240(15.6) | 42(36.2)* | < 0.001 |
Gestational hypertension, n(%) | 770(13.7) | 89(28.5)* | 226(19)* | 328(13.4)* | 117(7.6) | 10(8.6) | < 0.001 |
Premature rupture of membrane > 24 h, n(%) | 550(9.8) | 31(9.9)* | 159(13.4)* | 288(11.8)* | 67(4.3) | 5(4.3) | < 0.001 |
Apgar score at 1 min | 8(7, 9) | 6(4, 8)* | 8(6, 8)* | 8(7, 9)* | 9(8, 9) | 8(7, 9)* | < 0.001 |
Apgar score at 5 min | 9(8, 10) | 8(6, 9)* | 8(8, 9)* | 9(8, 10)* | 9(8, 10) | 9(8, 10) | < 0.001 |
PS in delivery room, n(%) | 54(0.9) | 4(1.2) | 19(1.6) | 18(0.7) | 12(0.7) | 1(0.8) | 0.127 |
Positive pressure ventilation in the delivery room, n(%) | 1096(19.6) | 105(33.6)* | 295(24.8)* | 420(17.2) | 252(16.3) | 24(20.6) | < 0.001 |
Endotracheal intubation in delivery room, n(%) | 475(8.5) | 81(25.9)* | 114(9.6)* | 129(5.3)* | 138(8.9) | 13(11.2) | < 0.001 |
Chest compressions in the delivery room, n(%) | 235(4.2) | 29(9.2)* | 62(5.2) | 68(2.7)* | 64(4.1) | 12(10.3)* | < 0.001 |