Perinatal characteristics of infants with acceptable spirometric data and those presumed to be alive but unavailable for follow up or without acceptable spirometric data at age 30
| Acceptable spirometric data(n = 383) | No acceptable spirometric data(n = 563) | p value | |
|---|---|---|---|
| Data are n (%), median (IQR), or mean (SD). | |||
| RDS, respiratory distress syndrome. | |||
| Maternal characteristics | |||
| Multiple pregnancy | 56 (15) | 57 (10) | 0.04 |
| Unplanned premature labour | 311 (81) | 473 (84) | 0.26 |
| Instrumental delivery | 207 (54) | 302 (54) | 0.90 |
| Complicated by hypertension | 33 (9) | 34 (6) | 0.13 |
| Gestational diabetes | 5 (1) | 8 (1) | 0.88 |
| Haemolytic disease | 20 (5) | 21 (4) | 0.27 |
| Median gestational age at entry (days) | 233 (217–243) | 231 (216–244) | 0.91 |
| Median entry/delivery interval (days) | 4.1 (1.9–32) | 4.6 (1.5–40) | 0.50 |
| Trial 1 | 243 (63) | 342 (61) | 0.40 |
| Betamethasone treatment | 181 (47) | 291 (52) | 0.18 |
| Neonatal characteristics | |||
| Male | 187 (49) | 336 (60) | 0.001 |
| Median gestational age delivery (days) | 245 (232–265) | 250 (238–269) | 0.04 |
| Term delivery | 121 (32) | 213 (38) | 0.05 |
| Mean birth weight (g) | 2341 (730) | 2464 (739) | 0.01 |
| Birth weight <1500 g | 49 (13) | 45 (8) | 0.02 |
| Mean birth weight z score | −0.40 (0.93) | −0.37 (1.00) | 0.63 |
| Birth weight <10th centile | 66 (17) | 88 (16) | 0.51 |
| Fetal distress | 54 (14) | 78 (14) | 0.92 |
| 5 min Apgar score >7 | 298 (78) | 449 (80) | 0.47 |
| RDS | 33 (9) | 36 (6) | 0.20 |
| RDS, moderate or severe | 22 (6) | 27 (5) | 0.52 |