LT: Welcome to this MRC podcast. Advances in neonatal care are improving outcomes for premature babies but there still seems to be a limit to what medical science can achieve. The Medical Research Council has been funding research into the survival prospects and long term health and social issues facing extremely premature babies. One of the lead researchers on the project, Kate Costeloe is professor of paediatrics at the Homerton University Hospital Neonatal Unit. The project called Epicure has covered two periods, Epicure 1 looked at all births before 26 weeks in 1995. Epicure 2 looked at all births before 27 weeks in 2006.
Professor Costeloe, what are the main findings of your study?
KC: Well the second study, Epicure 2 which relates to pre-term births in 2006 was set up with the primary aim of finding out just how many babies are surviving now and what problems those babies have and how those have changed since the study that we did in 1995. And the main findings have been firstly that it appears that in England numerically more babies are being admitted to neonatal units, babies born before 26 weeks, the actual numbers seem to have risen by around 30%. Furthermore, overall there's been an increase in survival of 12% from 40 to 52%. If we look at that by each week of pregnancy there's been a significant increase in survival for babies born both at 24 and 25 weeks. At 23 weeks there seems to be a trend towards increased survival but the numbers are smaller and it doesn't reach statistical significance so we can't be absolutely certain that there's increased survival at 23 weeks. When we look at the complications of prematurity in surviving babies, and we've looked particularly at brain damage as evidenced by the baby's ultrasound head scans, at long term oxygen dependency and at the number of babies whose eyes need to be treated for retinopathy, there seem to have been no changes in the proportion of surviving babies that have problems. Those surviving children will be assessed fully at the age of two and a half, those assessments will start later this year and we would anticipate that amongst surviving babies the pattern of impairments is going to be very similar to that that we found in the first study.
LT: This is indeed an extremely difficult area of medical practice, dealing with these very tiny babies. How have you found personally in your daily experiences of premature neonates, how do their experiences differ in 2008 compared to 1995?
KC: I think that in general the expectations, not just of parents but I think also of staff, have risen and I think that we expect babies to do better. I think the standards that people set themselves are higher. I think that there's been tremendous emphasis on improving the quality, considering things around the time of birth. I think obstetricians, more women are receiving antenatal steroids to help to protect the lungs and I think babies are born in slightly better condition. I think that neonatal paediatricians are making great strides to try and stop so many babies becoming cold soon after birth and being cold is very bad for babies and we know from the new study that many fewer babies are becoming cold than were. And I think there's a great deal of emphasis on the quality of care around the time of birth and I think that's in part probably what's driving the increase in survival. LT: And what do the findings mean about neonatal survival before 24 weeks?
KC: I think they're difficult to interpret. The numbers of such babies are very small. In the previous study there were fewer than 30 survivors below 24 weeks; that was in the whole of the UK and Ireland. This time we're looking just in England and we've actually at the moment we've got 51 survivors in the study below 24 weeks, but even so those numbers are fairly small. There appears to be a little bit of increase but I really can't be certain that that's real. On the other hand what does seem to be the case is that the babies are surviving a little bit longer and I would guess that if somebody comes back in another ten years or so's time and repeats the study, that probably they will find that survival is increasing at 23 weeks, but at the moment it's very marginal. LT: What are the main complications that a premature baby that young faces?
KC: Well the most serious and dramatic problem is when they have bleeding in the centre of the brain around the cerebral ventricles; that can be very serious and the baby may die very soon. This bleeding is typical in the first few days after birth. Many babies survive such bleeds but those babies are more likely to have longer term problems. They're also very vulnerable to severe infection; in the new study we've collected details of infection but we didn't in the first study so we can't make any comparisons. Many of them have severe problems with their lungs. In about 70% of these babies are still receiving oxygen shortly before they're due to be born and about 30% of them, 30 to 40% of them actually go home still needing oxygen. And those children are at greater risk of longer term respiratory problems. Smaller numbers but around about 20% of them are needing laser treatment to the back of the eye because they've got abnormalities on the back of the eye which related to their pre-term birth and to the fact that they'd been exposed to more oxygen than they would have been had they not been born so early. LT: And do you believe that medical science can progress to such an extent that survival will in the future be possible earlier and earlier? Or is there a threshold below which babies simply cannot survive and develop outside the womb?
KC: I personally suspect there is a threshold. I think the limiting organ is probably the lung but also the skin of these babies is fantastically fragile and sometimes breaks down and becomes a route of entry for infection. And I think there probably is a limit; I think the real challenge to us as paediatricians is to improve the outcomes for the babies that we can save, rather than to try to save babies born earlier and earlier.
LT: And how do you explain that your study has slightly different figures and numbers to a recently published study on the premature babies born in Trent in the last twelve years?
KC: Yes, well that's very interesting and something that's preoccupied me for the last few days since those data were published. The main differences are firstly that the Trent data, of course there are 55,000 births in Trent a year and the extreme prematurity rates aren't particularly high. So the numbers year on year aren't very big and the Trent analysis, what's been done is it's taken data over 12 years and analysed it in two 6 year blocks and even so, the numbers in the whole study are below, way below those in the numbers of the Epicure study from a single year from the whole country. The real differences are that in the two 6 year blocks there doesn't seem to have been an increase in the number of babies admitted to the units in the Trent region, whereas I'd say in the Epicure data we've seemed to see a 30% difference in the 11 years. That I find interesting and we will be doing more detailed regional analyses of the Epicure data and it may be that the population in Trent is relatively stable in comparison with that in some of the bigger conurbations where I suspect the numbers of pre-term births has gone up. The other thing is that at 23 weeks the Trent data shows absolutely no increase at all in survival; it goes in fact from 19 to 18%, whereas as I say, we seem to have a trend towards increased survival and I don't think I can explain that, I think we need to drill down further into the Epicure study when it's complete and try to understand better why some 23 week babies survive and why others don't and then go back and look at the Trent data. But as I say, the numbers in Trent are actually very small.
LT: This issue of survival at 23 weeks is obviously one that's of great concern at the moment to all those debating the human fertilisation and embryology bill in parliament. Some people would like to propose amendments to lower the abortion time limit. What message do you have for those who use Epicure to argue that the abortion time limit should be lowered or stay the same?
KC: Well it's a difficult one. Of course we've come at it from a completely different angle; we're paediatricians, we're interested in how well babies who are desperately wanted are doing and our ultimate hope is that we'll identify ways that we can actually improve the outcome for babies and I think our job is to present good data and present it clearly. I've had various encounters with MPs over the last few weeks, who of course in their minds the issue of whether or not a baby can survive is inextricably related to whether or not it's acceptable to consider aborting such a baby and I have to say in my own mind I feel that those are two completely separate issues. I feel our job is to present the data and it's then for the public and for MPs to decide whether or not because survival is increasing, whether or not that affects whether or not one can abort. LT: Laure Thomas KC: Kate Costeloe
