34 w (n: 302) 35 w (n: 504) 36 w (n: 1061) Total (n 1867) P
Male 168 (55.6%) 283 (56.1%) 604 (56.9%) 1055 (56.5%) 0.9*
Mean birth weight 2291.7 ± 411.1 2484.6 ± 422 g 2721 ± 423 g 1867 < 0.01+
Weight percentile AGA
239 (79.1%)
402 (79.8%)
853 (80.4%)
1494 (80%)
0.04*
LGA 42 (13.9%) 45 (8.9%) 97 (9.1%) 184 (9.9%)
SGA 21 (7%) 57 (11.3%) 111 (10.5%) 189 (10.1%)
Median NICU length of stay 7 d (5-12 d) 5 d (3-8 d) 3 d (3-5 d) 1867 <0.01§
NICU stay longer than 5 days 238 (78.8%) 279 (55.4%) 307 (28.9%) 824 (44.1%) <0.01§
Metabolic acidosis at birth No acidosis
290 (96%)
488 (96.8%)
1039 (97.9%)
1817 (97.3%)
0.01**
Mild acidosis 2 (0.7%) 1 (0.2%) 6 (0.6%) 9 (0.5%)
Moderate acidosis 1 (0.3%) 0 7 (0.7%) 8 (0.4%)
Severe acidosis 9 (3%) 15 (3%) 9 (0.8%) 33 (1.8%)
5’ Apgar score < 3 1 (0.3%) 2 (0.4%) 2 (0.2%) 5 (0.3%) 0.7**
Cardiopulmonary resuscitation 20 (6.6%) 27 (5.4%) 48 (4.5%) 95 (5.1%) 0.3*
Respiratory support No support
208 (68.9%)
411 (81.5%)
971 (91.5%)
1590 (85.2%)
< 0.01*
Invasive 5 (1.6%) 9 (1.8%) 13 (1.2%) 27 (1.4%)
Non invasive 89 (29.5%) 84 (16.7%) 77 (7.3%) 250 (13.4%)
Seizures 0 3 (0.6%) 0 3 (0.2%) 0.02**
Therapeutic hypothermia 1 (0.3%) 2 (0.4%) 4 (0.4%) 7 (0.4%) 0.9 **
Jaundice 145 (48%) 188 (37.3%) 241 (22.7%) 574 (30.7%) <0.01*
Sepsis 22 (7.6%) 27 (5.4%) 23 (2.2%) 72 (3.9%) < 0.01*
Hypoglycemia 92 (30.5%) 126 (25%) 196 (18.5%) 414 (22.2%) < 0.01*
Difficulty feeding 57 (18.9%) 70 (13.9%) 65 (6.1%) 192 (10.3%) < 0.01*
Cerebral lesion None
302 (100%)
502 (99.6%)
1056 (99.5%)
1860 (99.6%)
0.9**
Stroke 0 1 (0.2%) 2 (0.2%) 3 (0.2%)
Basal nuclei anomalies 0 1 (0.2%) 1 (0.1%) 2 (0.1%)
IVH >=2 0 0 2 (0.2%) 2 (0.1%)
Congenital anomalies none
267 (88.5%)
462 (91.6%)
990 (93.3%)
1719 (92.1%)
0.1**
Cardio vascular 10 (3.3%) 5 (1%) 21 (2%) 36 (1.9%)
CNS 1 (0.3%) 1 (0.2%) 2 (0.2%) 4 (0.2%)
Gastrointestinal 1 (0.3%) 4 (0.8%) 4 (0.4%) 9 (0.5%)
Genito-urinary 1 (0.3%) 7 (1.4%) 3 (0.3%) 11 (0.6%)
Others 22 (7.3%) 25 (5%) 41 (3.8%) 88 (4.7%)
Chromosomal anomalies 1 (0.3%) 4 (0.8%) 4 (0.4%) 9 (0.5%) 0.5**
Adverse Composite Neonatal Outcome 82 (27.1%) 89 (17.7%) 85 (8%) 256 (13.7%) <0.01*
Hypoglycemia and difficulty feeding 129 (42.7%) 170 (33.7%) 239 (22.5%) 538 (28.8%) <0.01*
Metabolic acidosis/ resuscitation 20 (6.6%) 27 (5.4%) 48 (4.5%) 95 (5.1%) 0.3*
Respiratory support 94 (31.1%) 93 (18.4%) 90 (8.5%) 277 (14.8%) <0.01*