Table 2.
Major neonatal morbidity among babies born between 22 and 26 weeks’ gestation who survived to discharge, England, 2006. Figures are numbers (percentage, 95% confidence interval)
| Gestational age (weeks) | P value* | ||||||
|---|---|---|---|---|---|---|---|
| 22 | 23 | 24 | 25 | 26 | 22-26 | ||
| Total survivors | 3 | 66 | 178 | 346 | 448 | 1041 | |
| Major morbidities | |||||||
| Bronchpulmonary dysplasia (supplementary oxygen at 36 weeks postmenstrual age) | 3 (100, 29 to 100) | 57 (86, 76 to 94) | 142 (80, 73 to 85) | 231 (67, 62 to 72) | 272 (61, 56 to 66) | 705 (68, 65 to 71) | <0.001 |
| Severe bronchopulmonary dysplasia † | 2 (67, 9 to 99) | 42 (64, 51 to 75) | 95 (53, 46 to 61) | 136 (39, 34 to 45) | 151 (34, 29 to 38) | 426 (41, 38 to 44) | <0.001 |
| Retinopathy stage ≥3 (in at least one eye) | 1 (33, 1 to 91) | 28 (42, 30 to 55) | 63 (36, 29 to 43) | 73 (21, 17 to 26) | 48 (11, 8 to 14) | 213 (21, 18 to 23) | <0.001 |
| Laser treatment for retinopathy | 0 (0, 0 to 71) | 22 (33, 22 to 46) | 48 (27, 21 to 34) | 57 (7, 13 to 21) | 39 (9, 6 to 12) | 166 (16, 14 to 19) | <0.001 |
| Severe abnormality on last available cerebral ultrasound scan‡ | 1 (33, 1 to 91) | 4 (6, 2 to 15) | 27 (15, 10 to 21) | 50 (15, 11 to 19) | 53 (12, 9 to 15) | 135 (13, 11 to 15) | 0.87 |
| Laparotomy for necrotising enterocolitis | 1 (33, 1 to 91) | 4 (6, 2 to 15) | 20 (11, 7 to 17) | 25 (7, 5 to 11) | 29 (6, 4 to 9) | 79 (8, 6 to 9) | 0.020 |
| Other morbidities | |||||||
| z score <−2 at 40 weeks postmenstrual age: | |||||||
| Weight | 1 (33, 1 to 91) | 37 (57, 44 to 69) | 90 (51, 43 to 58) | 143 (43, 37 to 48) | 183 (41, 37 to 46) | 454 (44, 41 to 48) | <0.001 |
| Occipitofrontal circumference | 0 (0 to 71) | 29 (46, 33 to 59) | 62 (36, 29 to 44) | 78 (25, 20 to 30) | 82 (20, 16 to 24) | 251 (26, 23 to 29) | <0.001 |
| Treated patent ductus arteriosus§ | 2 (67, 9 to 99) | 50 (77, 65 to 86) | 118 (68, 61 to 75) | 162 (49, 44 to 55) | 168 (41, 36 to 46) | 500 (51, 46 to 54) | <0.001 |
| Patent ductus arteriosus treated surgically | 2 (67, 9 to 99) | 24 (36, 25 to 49) | 41 (23, 17 to 30) | 59 (17, 13 to 22) | 40 (9, 6 to 12) | 166 (16, 14 to 18) | <0.001 |
| Gram negative bacteraemia >72 hours after birth | 0 (0, 0 to 71) | 12 (18, 10 to 30) | 22 (13, 8 to 18) | 19 (6, 3 to 9) | 28 (6, 4 to 9) | 81 (8, 6 to 10) | 0.001 |
| Coagulase negative staphylococcal bacteraemia >72 hours after birth | 3 (100, 29 to 100) | 37 (56, 43 to 68) | 106 (61, 53 to 68) | 179 (52, 47 to 58) | 189 (43, 38 to 48) | 514 (50, 47 to 53) | <0.001 |
| Positive fungal blood culture at any age | 0 (0, 0 to 71) | 2 (3, 0 to 11) | 9 (5, 2 to 9) | 17 (5, 3 to 8) | 8 (2, 1 to 4) | 36 (4, 2 to 5) | 0.018 |
| Survival without major morbidity | 1 (33, 1 to 91) | 15 (23, 13 to 35) | 52 (29, 23 to 37) | 133 (38, 33 to 44) | 222 (50, 45 to 54) | 423 (41, 38 to 44) | <0.001 |
*P value for association of gestational age using either logistic regression or regression with gestational age in decimal weeks.
†Severe bronchopulmonary dysplasia defined as still receiving mechanical ventilatory support and/or in ≥30% or >0.1L/min supplementary oxygen.16
‡Severe abnormality on cerebral ultrasonography defined as scan showing one or more of ventriculomegaly, parenchymal cysts, haemorrhagic parenchymal infarction.
§Patent ductus arteriosus treated with either indometacin, ibuprofen, or surgical ligation
¶Major morbidity defined as any of: severe abnormality on cerebral ultrasonography, severe bronchopulmonary dysplasia, retinopathy of prematurity stage 3 or more, or laparotomy for necrotising enterocolitis