VLBW infant characteristics at the 39 NICUs, born 2000–2014
| Number of participating NICUs | 39 |
| Total VLBW infants | 58 272 |
| VLBW infant admissions per NICU per year, mean (range) | 111 (18–322) |
| Gestational age, weeks, mean (SD) | 28.2 (3.0) |
| Birth weight, grams, mean (SD) | 1031 (301) |
| Inborn, %, mean (range) | 85 (0–99) |
| Caesarean section, %, mean (range) | 70 (58–79) |
| Antenatal corticosteroid, %, mean (range) | 79 (59–85) |
| Major birth defects, %, mean (range) | 6 (2–13) |
| Male sex, %, mean (range) | 51 (48–54) |
| Survived to discharge, %, mean (range) | 86 (77–94) |
NICU, neonatal intensive care unit; VLBW, very low birth weight.