Table 3
Morbidity outcomes
| Infants <1500 g | |||
|---|---|---|---|
| Morbidity outcomes | 1986 cohort | 1998–1999 cohort | p Value |
| Values are number (%). | |||
| *Of infants surviving to 28 days. | |||
| †Of infants surviving to 36 weeks postmenstrual age. | |||
| ‡Of infants surviving to discharge. | |||
| §Of those examined. | |||
| ¶In 1998–1999, 40 (4%) infants had grade 2 IVH and seven (1%) infants had grade 3 IVH. | |||
| Chronic lung disease | |||
| Oxygen dependency at 28 days* | |||
| <1000 g | 68 (73) | 196 (58) | 0.007 |
| 1000–1499 g | 68 (26) | 94 (14) | <0.001 |
| <1500 g | 136 (39) | 290 (29) | 0.001 |
| Oxygen dependency at 36 weeks† | |||
| <1000 g | 37 (42) | 110 (33) | 0.14 |
| 1000–1499 g | 43 (17) | 43 (7) | <0.001 |
| <1500 g | 80 (23) | 153 (16) | 0.002 |
| Retinopathy of prematurity (ROP)‡ | |||
| Examined for ROP | |||
| <1000 g | 83 (97) | 305 (93) | 0.23 |
| 1000–1499 g | 230 (91) | 391 (61) | <0.001 |
| <1500 g | 313 (93) | 696 (72) | <0.001 |
| Stages 1 or 2 ROP§ | |||
| <1000 g | 29 (35) | 83 (27) | 0.17 |
| 1000–1499 g | 24 (10) | 40 (10) | 0.94 |
| <1500 g | 53 (17) | 123 (18) | 0.77 |
| Stages 3 or 4 ROP§ | |||
| <1000 g | 11 (13) | 19 (6) | 0.03 |
| 1000–1499 g | 1 (1) | 2 (1) | 1.00 |
| <1500 g | 12 (4) | 21 (3) | 0.50 |
| Intraventricular haemorrhage (IVH)‡ | |||
| Examined for IVH | |||
| <1000 g | 70 (81) | 325 (99) | <0.001 |
| 1000–1499 g | 179 (71) | 596 (92) | <0.001 |
| <1500 g | 249 (74) | 921 (94) | <0.001 |
| Grades 1§ | |||
| <1000 g | 19 (27) | 28 (9) | <0.001 |
| 1000–1499 g | 40 (22) | 42 (7) | <0.001 |
| <1500 g | 59 (24) | 70 (8) | <0.001 |
| Grades 2 or 3§ | |||
| <1000 g | 14 (20) | 28 (9) | 0.005 |
| 1000–1499 g | 14 (8) | 19 (3) | 0.007 |
| <1500 g | 28 (11) | 47 (5)¶ | <0.001 |
| Grade 4§ | |||
| <1000 g | 5 (7) | 9 (3) | 0.07 |
| 1000–1499 g | 4 (2) | 14 (2) | 1.00 |
| <1500 g | 9 (4) | 23 (2) | 0.34 |
