<34周(n = 115)

≥34周(n = 79)

X²

P值

NRDS

26 (22.6%)

4 (5.1%)

11.028

0.001

围产期因素

43 (37.4%)

42 (53.2%)

4.733

0.030

SGA

8 (7.0%)

16 (20.3%)

7.637

0.006

妊高症

28 (24.3%)

30 (38.0%)

4.149

0.042

宫内窘迫

30 (26.1%)

15 (19.0%)

1.325

0.250

免疫因素

7 (6.1%)

8 (10.1%)

1.071

0.301

NEC

7 (6.1%)

1 (1.3%)

0.145

DIC

4 (3.5%)

4 (5.1%)

0.718

染色体异常

2 (1.7%)

2 (2.5%)

1.000

败血症

14 (12.2%)

7 (8.9%)

0.533

0.466

早发败血症

7 (6.1%)

5 (6.7%)

1.000

晚发败血症

7 (6.1%)

2 (2.5%)

1.338

0.247

其他原因

12 (10.4%)

11 (13.9%)

0.546

0.460