Comparison of survival rates of extremely preterm infants with a gestational age between 22 and 25 completed weeks in Switzerland, the UK, Finland, the USA and Sweden (all are population-based, multicentre studies including inborns and outborns)
| Switzerland | UK Trent | Finland | USA (NICHD) | Sweden | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 16 | Current study | 20 | 19 | 5 | 4 | 2 | |||||
| Reference | Overall | CTC range | Overall | CTC range | |||||||
| Time period | 2000 to 2004 | 2005 to 2009 | 1994 to 1999 | 2000 to 2005 | 1996 to 1997 | 1999 to 2000 | 1998 to 2003 | 2003 to 2007 | 2004 to 2007 | ||
| Total population | |||||||||||
| Live births, N | 516 | 551 | 682 | 669 | 152 | 160 | 4446 | 4160 | 707 | ||
| Survivors, N | 180 | 192 | 174 | 236 | 57 | 75 | 2267 | 2077 | 497 | ||
| Survivors, % | 35% | 16–53% | 35% | 20–53% | 26% | 35% | 38% | 47% | 51% | 50% | 70% |
| 22 weeks | |||||||||||
| Live births, N | 18 | 54 | 81 | 69 | 21 | 19 | NA | 421 | 51 | ||
| Survivors, N | 0 | 0 | 0 | 0 | 1 | 0 | NA | 25 | 5 | ||
| Survivors, % | 0% | 0% | 0% | 0% | 0% | 0% | 5% | 0% | 5% | 6% | 10% |
| 23 weeks | |||||||||||
| Live births, N | 82 | 101 | 148 | 131 | 36 | 29 | NA | 871 | 101 | ||
| Survivors, N | 4 | 4 | 15 | 12 | 4 | 7 | NA | 226 | 53 | ||
| Survivors, % | 5% | 0–20% | 4% | 0–27% | 10% | 9% | 11% | 24% | 26% | 26% | 52% |
| 24 weeks | |||||||||||
| Live births, N | 158 | 179 | 198 | 227 | 44 | 53 | NA | 1370 | 144 | ||
| Survivors, N | 47 | 55 | 40 | 82 | 18 | 25 | NA | 748 | 96 | ||
| Survivors, % | 30% | 0–53% | 31% | 0–73% | 20% | 36% | 41% | 47% | 56% | 55% | 67% |
| 25 weeks | |||||||||||
| Live births, N | 258 | 217 | 255 | 242 | 51 | 59 | NA | 1498 | 205 | ||
| Survivors, N | 129 | 133 | 119 | 142 | 34 | 43 | NA | 1078 | 167 | ||
| Survivors, % | 50% | 38–74% | 61% | 38–82% | 47% | 59% | 67% | 73% | 75% | 72% | 81% |
CTC, centre-to-centre; NICHD, National Institute of Child Health and Human Development; NA, not available.