Consortium On IVF In Europe

November 28, 2006

OBGYN.net Conference CoverageFrom the ESHRE 2000 Conference Bologna, Italy

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Dr. Hans van der Slikke:  "We're at the ESHRE 2000, and just a few moments ago Professor Karl Nygren from Sweden presented the news on IVF in Europe. This presentation was done in name of the consortium that registered these numbers. Professor Nygren, please tell us about this consortium, how is it composed?"

Professor Karl Nygren:  "It's composed from the older existing registers on IVF outcomes in eighteen countries in Europe. We called them together and we formed a consortium to pool our data for the first time for Europe so that we can make comparisons and also to make it possible for patients and professionals to know where they are sort of in this business because it's a very dynamic situation, many, many things change over the years so we have a common interest in all of the countries in Europe to do this and this is the first presentation today."

Dr. Hans van der Slikke:  "Can you tell us what's the importance of having these figures?"

Professor Karl Nygren:  "The importance is that you will be able to make comparisons. You can make comparisons within Europe, in different countries, and also to other continents like the United States. The importance of making comparisons is to find out and make sure whether you are on the right track or not because if you compare yourself with other countries, you may find out that your results are perhaps not as good as they should be. You can find out about side effects that you have figures on that are not perfect so it's a monitoring system. The monitoring is that you will see where you are in geography you can look out, you can look up from your microscope, look around, and see if you're car is driving in the middle of the road."

Dr. Hans van der Slikke:  "Does the European car drive in the middle of the road?"

Professor Karl Nygren:  "Yes, I think so. We're driving in the middle of the road in Europe but there are also differences within Europe. Perhaps if I can make some comparison with other regions like the United States - this report then tells us of that our pregnancy rate, our success rate I would say, is somewhat lower than it is in the United States. But very importantly, the rate of multiple pregnancies here is much lower than in the United States. So that comparison is very important because it tells you that you may have better results, if you wish, by putting in many more embryos but the price is that you will have a much higher multiple pregnancy rate. A multiple pregnancy is the only identifiable factor with negative consequences to the children but the consequences are relatively severe because multiple pregnancy means prematurity, and prematurity means the increased risk of mortality and morbidity being higher than otherwise." 

Dr. Hans van der Slikke:  "You compared these European figures with the United States but in showing us these figures, you also showed that there's a big difference in the European states."

Professor Karl Nygren:  "Yes, and the difference is the following, I think the overall success rate in each country is fairly constant, it's about 23% deliveries per embryo transfer, take home baby rate if you like. That is fairly constant in all the countries but what differs is, again, the rate of multiple pregnancy which in some regions like in the north of Europe, this rate of multiple pregnancy is now low whereas in the south and the east it is much higher. So again, this comparison within northern and southern Europe shows us the same difference actually as been with Europe as a whole and the United States as a whole but the situation is also dynamic. We know not from the report but from history that the situation was similar in the northern countries, five, six, seven years ago. By reducing the number of embryos replaced voluntarily because we saw what was going to happen, we were able to lower the multiple pregnancy rate to a much lower level now but we were afraid that we would then lose efficacy. That the pregnancy rate, the delivery per ET rate to take home baby rate, would go down but alas, it did not. It actually did not so we succeeded to keep the same efficacy while we were able to reduce the multiple pregnancy rate. We were afraid that that could not be done but now we know that it definitely can be done so I think that is one of the conclusions from such a comparison that it can be done. It can be used perhaps to talk to professionals and patients in other regions of the world where they have a very high pregnancy rate and persuade them that that is not necessary and that it can actually be reduced and that would be a very good thing."

Dr. Hans van der Slikke:  "About how many cycles did you report this afternoon?"

Professor Karl Nygren:  "The report covers one particular year which was all the treatments. It started in 1997, and it's just over 200,000 treatment cycles." 

Dr. Hans van der Slikke:  "That's a lot."

Professor Karl Nygren:  "Yes, again, if we compare it to what we call the report which covers the United States, our report is three times larger than theirs which means that the IVF activity per person is very much higher here than in the United States. Actually, if you look at the figures, it's about twice as high here. I'm not sure that we have been aware of that fact before so the report shows us now that the bulk of the activity on this field is going on in Europe. More than half of all treatments of IVF in the world is being done in Europe and within Europe, and the UK, France, and Germany together do more than half of our cycles so they do about 100,000 cycles. All this resulted for that one year for the birth of approximately 50,000 children, and now the world figure is about 100,000 per year born children, half of them from Europe."

Dr. Hans van der Slikke:  "Yes, that's a lot. Can you tell us how exact these figures are? Is this the same in all countries or are there differences in the different countries in the way of bookkeeping these cycles?"

Professor Karl Nygren:  "Yes, it is true that the registers in the different countries work in a different way so the report has actually gathered together already existing data and that is the only possibility that we have now. This means that we have taken the data that exists and tried to put them together in an intelligent way so that we can do the comparisons but it is true that some caution is there. We're not certain to the very last per mil but the figures that we present on the whole is correct but there might be slight differences in different countries on the validity. Some countries report complete results, all treatments are reported. In other countries in Europe that has not been possible yet so their register may not cover all of the activities in that country. Of course, the goal is we want to recommend countries to try and do data collection that are complete and that are validated but to date, it varies a little bit but I think we can handle that."

Dr. Hans van der Slikke:  "Talking about multiple pregnancies, is there in any of the countries any legal force to transfer two eggs only or even one?"

Professor Karl Nygren:  "The only country I'm aware of that this is something illegal or not, I think, is in the United Kingdom where you are not allowed to put in more than three eggs. In practice in my country of Sweden, we do not put in more than two eggs anyway but law does not state it. But on your question - yes, in England it's stipulated no more than three but I know that in the UK they are discussing whether perhaps one should lower that to two. Our slogan as it were back home in Sweden and also in other parts of Europe is to persuade people that they can have as many children as they like, we hope, but they should have them one at a time. One at a time is better than having them in a bunch."

Dr. Hans van der Slikke:  "You agreed with one of our colleagues who said we're now at the point of thinking about multiple pregnancy as a complication of IVF and ICSI and not as a positive result."

Professor Karl Nygren:  "Yes, it's another way of putting it quite elegantly. I don't think all couples today would agree that it would be a side effect actually because it must also be said that at least for twins, if we try to be very precise, what we are most afraid of is damage to the brain according to prematurity, and that is cerebral palsy. So what is the risk of cerebral palsy? Our report here today doesn't say that but we have had a recent report from Sweden, the first big one in the world, showing us the following figures. The background risk to have a CP child in all the populations: Sweden is 0.15%, after IVF it is 0.5% so it's almost four times higher. But the actual risk is very low indeed but there is a risk and those cases are, of course, terrible so they should be avoided. But the risk increases much more if we're talking about triplets or quadruplets and so I think there is a problem today if we look at the frequency of duplex over the European countries, it's not that different. The difference is in triplets and quadruplets, and in Scandinavia this figure today is zero whereas in the southern European countries it is a little bit below ten, 7%-8% triplets. That means that many of the children belong to sets of triplets and then we are talking about much higher risks than with twins." 

Dr. Hans van der Slikke:  "Do you have figures about CP incidence in triplets?"

Professor Karl Nygren:  "No, I don't have the actual risk with me now because it doesn't happen that often in the background population, it's almost very difficult to know so we have to deduct it from seeing that triplets are very much more premature. So I can't give you the exact risk but we have, of course, numbers of mortality and things but on this particular question. Today, I don't know the exact figure."

Dr. Hans van der Slikke:  "So we all agree that it's very important to reduce the number of multiple pregnancies because of the health of the newborns. I think you illustrated this perfectly this afternoon with this report on which I can congratulate you because I think it's one of the highlights of this Conference. You told us it was a preliminary report, when can we expect to see the figures in print?"

Professor Karl Nygren:  "We will finalize the report through our friends in the consortium within one to two months and then we will try and have it publicized in Human Reproduction, our ESHRE's own journal. So I expect that that would be within a limited number of months, this autumn."

Dr. Hans van der Slikke:  "Thank you very much, Professor Nygren."