Table 1. Perinatal baseline characteristics and outcomes of discharged infants with BW ≤ 1500 g.
| Characteristics | BW ≤500 g (n = 6) |
BW 501–750 g (n = 270) |
BW 751–1000 g (n = 761) |
Subtotal BW≤1000g (n = 1037) | BW 1001–1250 g (n = 1060) |
BW 1251–1500 g (n = 1284) |
BW Total ≤ 1500 g (n = 3381) |
|---|---|---|---|---|---|---|---|
| Antenatal steroid, two doses, n (%) | 1 (16.7%) | 117 (43.3%) | 351 (46.1%) | 469 (45.2%) | 467 (44%) | 514 (40%) | 1450 (42.9%) |
| Preeclampsia, n (%) | 1 (16.7%) | 100 (37%) | 217 (28.5%) | 318 (30.6%) | 288 (27.2%) | 283 (22%) | 889 (26.3%) |
| Gestational diabetes, n (%) | 1 (16.7%) | 14 (5.2%) | 45 (5.9%) | 60 (5.8%) | 60 (5.7%) | 71 (5.5%) | 191 (5.6%) |
| Chorioamnionitis, n (%) | - | 18 (6.7%) | 107 (14%) | 125 (12%) | 95 (9%) | 113 (8.8%) | 333 (9.8%) |
| IVF pregnancy, n (%) | 1 (16.7%) | 32 (11.8%) | 81 (10.6%) | 114 (11%) | 115 (10.8%) | 151 (11.8%) | 380 (11.2%) |
| Multiple births | |||||||
| Twin, n (%) | 1 (16.7%) | 41 (15.2%) | 124 (16.3%) | 166 (16%) | 201 (19%) | 322 (25.1%) | 689 (20.4%) |
| Triplet, n | - | 5 (1.8%) | 35 (4.6%) | 40 (3.9%) | 47 (4.4%) | 59 (4.6%) | 146 (4.3%) |
| Vaginal delivery, n (%) | - | 38 (14%) | 109 (14.3%) | 147 (14.2%) | 120 (11.3%) | 181 (14.1%) | 448 (13.2%) |
| Gestational age (weeks)* | 25.3±2.2 | 26.1±2 | 27.5 ± 1.9 | 27±2 | 29.1±1.9 | 30.5±1.8 | 29±2.4 |
| Birth weight, (grams)* | 444±41 | 665±65 | 898 ± 74 | 835±128 | 1132 ± 71 | 1386 ± 71 | 1137 ± 245 |
| Male gender, n (%) | 3 (50%) | 113 (41.8%) | 343 (45.1%) | 459 (44.3%) | 513 (48.4%) | 630 (49.1%) | 1602 (47.4%) |
| SGA, n (%) | 6 (100%) | 108 (40%) | 184 (24.2%) | 298 (28.8%) | 232 (21.9%) | 222 (17.3%) | 752 (22.2%) |
| Resuscitation at birth, n (%) | 5 (83.3%) | 223 (82.6%) | 513 (67.4%) | 741 (71.4%) | 536 (50.6%) | 494 (38.5%) | 1771 (52.4%) |
| RDS, n (%) | 6 (100%) | 255 (94.4%) | 627 (82.4%) | 888 (85.7%) | 763 (71.2%) | 712 (55.4%) | 2363 (69.9%) |
| Surfactant treatment, n (%) | 6 (100%) | 241 (89.2%) | 565 (74.2%) | 812 (78.3%) | 622 (58.7%) | 534 (41.6%) | 1968 (58.2%) |
| Duration of invasive mechanical ventilation (days)** | 3 (0–48) | 14 (2–42) | 3 (0–15) | 5 (0–21) | 1 (0–4) | 0 (0–2) | 1 (0–6) |
| Duration of noninvasive ventilation (days)** | 26 (7–89) | 19 (10–30) | 12 (4–24) | 14 (5–26) | 5 (2–12) | 3 (1–6) | 5 (2–14) |
| Total days on oxygen (days)** | 54 (26–135) | 68 (40–95) | 39 (15–64) | 47 (20–75) | 18 (7–41) | 8 (4–20) | 19 (6–46) |
| PDA requiring treatment, n (%) | 4 (66.7%) | 139 (51.5%) | 276 (36.3%) | 419 (40.4%) | 238 (22.4%) | 180 (14%) | 837 (24.8%) |
| Intracranial hemorrhage (> Grade II), n (%) |
- | 39 (14.4%) | 50 (6.6%) | 89 (8.6%) | 49 (4.7%) | 46 (3.6%) | 184 (5.4%) |
| Late-onset sepsis, n (%) | 5 (83.3%) | 220 (81.5%) | 451 (59.3%) | 676 (65.2%) | 421 (39.8%) | 338 (26.3%) | 1435 (42.4%) |
| Culture proven, n (%) | 2 (33,3%) | 119 (44.1%) | 235 (30.9%) | 356 (34.3%) | 202 (19%) | 157 (12.2%) | 715 (21.1%) |
| NEC (≥ Stage II), n (%) | 1 (16.7%) | 45 (16.7%) | 96 (12.6%) | 142 (13.7%) | 94 (8.9%) | 70 (5.4%) | 306 (9.1%) |
| BPD, n (%) | 4 (66.7%) | 187 (69.3%) | 285 (37.4%) | 476 (45.9%) | 205 (19.3%) | 119 (9.3%) | 800 (23.7%) |
| Any degree of ROP, n (%) | 3 (50%) | 224 (82.9%) | 507 (66.6%) | 734 (70.8%) | 428 (40.4%) | 267 (20.8%) | 1429 (42.3%) |
| Severe ROP, n (%) | 1 (16.7%) | 120 (44.4%) | 151 (19.8%) | 272 (26.2%) | 73 (6.9%) | 32 (2.5%) | 377 (11.1%) |
*Values are presented as mean±SD
** Values are presented as median, and IQR (interquartile range) are given in parenthesis
BW: Birth weight, IVF: Invitro fertilization, SGA:Small for gestational age, RDS:Respiratosy distress syndrome, PDA: Patent ductus arteriosus, NEC:Necrotizing enterocolitis, BPD:Bronchopulmonary dysplasia, ROP: Retinopathy of prematurity