Background The management of infants born at less than 24 weeks gestation (<24 w) remains contentious. In a large population based cohort 1993–2008 we previously showed no appreciable increase in long-term survival for liveborn infants <24 w, although median age at death increased over each successive 5-year epochs. We aimed to review recent changes in survival <24 w, and to determine risk factors that might predict non-survival at an earlier age.

Methods Cases (live-born infants at 22–23w) were identified using a well-validated population based database (Regional Maternity Survey Office, Northern Region, UK) for the 5-year epoch 2008–2012. We included cases still alive at 6 h of age, in order to identify a group where the intention to provide active management appears likely. Survivors were identified from unit databases of the 4 tertiary level neonatal units, and individual case notes reviewed.

Results During the study period 55 infants (56% male) born at 22–23w (n = 2 at 22w) were alive at 6 h (birth prevalence ˜4:10,000). Of these 24/55 infants (44%) were alive at 12 months age (50% male); 18/24 survivors received at least one dose of steroids. Median survival of non-survivors was 2.65 days (excludes one case known to have died at >2 years age). 7/31 non-survivors had a laparotomy, 3 had retinopathy of prematurity (ROP) treatment, 3 had PDA ligation, and only 2/31 ever achieved full feeds. Amongst survivors, 20/24 required some form of invasive surgery/intervention (4 laparotomy, 2 other surgery, 15 laser ROP, 2 Avastin for ROP, and 14 PDA ligation.) There was no significant difference in birthweight between survivors and non-survivors. Initial analysis did not identify early postnatal factors that enabled clear identification of infants who subsequently died.

Conclusion Survival at <24 w has increased dramatically in this population over the last few years, but was not associated with a prolonged period of intensive care in those who did not survive. However, there was considerable morbidity (e.g. surgical procedures) in both groups. Increased survival may be due to several factors, and will be affected by clinician and parental attitudes.