Main content

Saturated Fats, Moles, Egg Freezing

Dr Mark Porter presents recent research into saturated fats, advice on checking moles: how to spot the innocent from the sinister, and success rates for egg freezing and pregnancy.

Recent research was widely reported as concluding that 30 year old guidance to limit saturated fats had been overturned and should never have been introduced - and that we can now eat as much butter, cheese, sausages and pies as we like.

But, as ever, the real story is a bit different. Inside Health debates the real evidence and hears from Sweden that rumours of change in its guidance have also been misreported.

As big companies try to attract female employees by offering 'egg freezing' as a corporate carrot, Dr Mark Porter examines the success rates and implications for women wanting to start a family.

And checking your moles - how to tell the difference between the sinister and the innocent.

Available now

28 minutes

Programme Transcript - Inside Health

Downloaded from Ìý

THE ATTACHED TRANSCRIPT WAS TYPED FROM A RECORDING AND NOT COPIED FROM AN ORIGINAL SCRIPT.Ìý BECAUSE OF THE RISK OF MISHEARING AND THE DIFFICULTY IN SOME CASES OF IDENTIFYING INDIVIDUAL SPEAKERS, THE Â鶹Éç CANNOT VOUCH FOR ITS COMPLETE ACCURACY.

Ìý

Ìý

INSIDE HEALTH

ÌýÌýÌýÌýÌýÌýÌýÌýÌýÌýÌý

Programme 9.

Ìý

TX:Ìý 03.03.15Ìý 2100-2130

Ìý

PRESENTER:Ìý MARK PORTER

Ìý

PRODUCER:Ìý ERIKA WRIGHT

Ìý

Ìý

Porter

Coming up today – moles, and how to tell the difference between an innocent and a sinister one.

Ìý

And freezing your eggs - more women are leaving it later to start a family and turning to private clinics to help them preserve their fertility. But it’s not quite as straightforward as some may think.

Ìý

Clip

It seems also sometimes in societal debates that you go to this clinic and you have a consultation and the same afternoon we freeze your oocytes and you’re done.Ìý It’s a rather intensive procedure, it’s very similar to doing an in vitro fertilisation procedure.Ìý The general assumption sometimes is that if you’ve frozen your oocytes this means that you will surely get a child and this is absolutely not the situation.

Ìý

Porter

More on egg freezing later.

Ìý

But first new research into fats or, to be more specific, media coverage of a study questioning the evidence behind guidelines on how much fat we should be eating.

Ìý

Clip

Food fight.Ìý Row over saturated fat advice.

Ìý

Fat guidelines lack solid scientific evidence.

Ìý

Saturated fat may not be the enemy.

Ìý

Porter

Research published by the online journal Open Heart was widely reported as concluding that 30 year old guidance to limit saturated fat intake to 10% or less of our daily calorie intake should never have been introduced. And the study has been used by some as further proof that saturated fats are not linked to heart disease and that we can now eat as much butter, cheese, sausages and pies as we like.

Ìý

But, as ever, the real story is a bit different.Ìý So to debate the issue:Ìý Inside Health’s Dr Margaret McCartney, Nick Sculthorpe who’s senior lecturer in clinical exercise physiology and one of the authors of the paper and Christine Williams, Professor of Human Nutrition at the University of Reading.

Ìý

Williams

The most worrying statement made following the publication of this paper was the guidelines have been reversed, we don’t need to worry about saturated fat.Ìý I was very concerned about that because of course the guidelines haven’t been reversed and no single paper, however good or however strong, is going to immediately reverse the evidence.Ìý Now I don’t think the authors of the paper intended that to happen but of course these are the sorts of things that do happen.

Ìý

Porter

Well Nick Sculthorpe’s in our Glasgow studio, he’s one of those authors.Ìý Nick, were you happy with the way, first of all, that your research was portrayed?

Ìý

Sculthorpe

I’d have to say not entirely happy.

Ìý

Porter

What worried you about it?

Ìý

Sculthorpe

Well we’ve been put in the position where we’re having to defend a number of statements that we never really made in the paper and questions we didn’t address in the paper.Ìý So the whole issue of fat is now good, eat as much butter as you like – we didn’t address any of that.

Ìý

Porter

Well let’s be clear then.Ìý Can you tell us what you did address?

Ìý

Sculthorpe

Okay.Ìý If you’ve got recommendations that aren’t transparent and rational it’s very difficult for the population to buy into them.Ìý So we wanted to go back to the beginning and say right, so what was the evidence at the beginning, at the start.Ìý So we looked at the RCT – which is randomised control trial evidence that was available in the UK and the US at the time the guidelines were brought it.

Ìý

Porter

Because this is going back to the rationale behind guidance that was introduced in the States in the ‘70s and in the UK here in the ‘80s?

Ìý

Sculthorpe

Yes that’s correct.

Ìý

Porter

So what did – what was your conclusion?

Ìý

Sculthorpe

On the face of it the conclusion is that the RCT evidence didn’t support it because in neither the control groups or the cohort that got the dietary intervention was any difference between those two groups in terms of mortality.

Ìý

Porter

There was no evidence that switching to a low saturated fat diet actually improved outcomes?

Ìý

Sculthorpe

That’s correct on the face of it.Ìý However, the devil is in the detail and the real issue is that none of these studies were really designed to address that question.Ìý And if you wanted to push me and say what did the paper really show – it showed that if you alter the diet of older men who’ve already had heart disease or heart attacks and follow them for five years has minimal difference.

Ìý

Porter

Which, Christine, is very different from the way that it was portrayed.

Ìý

Williams

It is very different.Ìý But I would want to make one very important point in relation to the way in which advice on diet for healthy populations is put together.Ìý Randomised control trials are not necessarily the pinnacle of the evidence, that’s the whole point.Ìý In this case, as has just been said, these were men – mostly men I think, all men actually, the studies were all men – who’d had a heart attack before.Ìý Now we know that they are well down the line of disease and the diet that would possibly reverse that is not necessarily the same diet that we should be advising the whole population to take.Ìý So dietary experts they do listen to randomised control trial data but they don’t necessarily take it as the best data, which is what the pharmaceutical industry, the biomedical industry which is used to working on drug trials, that’s what they do because drugs are given to people who are already ill, diets are not necessarily.Ìý So I was in a position to the scientists in that respect because I think they misrepresented what the science base of nutrition is all about.

Ìý

Porter

Margaret McCartney, what’s your take on this situation?

Ìý

Porter

Well part of the problem that we have is that we’re not relying on randomised control trials and had we had a randomised control trial that was now 40 years old comparing say the Mediterranean diet with people who are not told to follow it we’d have really good data by now.

Ìý

Porter

So what you’re suggesting is that what we should have done is taken a large number of people, put half of them on one diet and half of them on another and then compare the outcomes over many years?

Ìý

McCartney

Well that would have really helped, that would have given us really good data.Ìý And the problem with so many public health interventions is that we simply don’t do this, we rely on slightly grubby data, data that’s not really clean, that doesn’t separate out clearly one control group from your intervention group.Ìý And because of that it means that there’s lots of bias and there’s lots of uncertainties, far more now than we would have had if we’d have done really high quality…

Ìý

Porter

But you can say Margaret that we shouldn’t have started – we shouldn’t have started from here but that’s where we started from, we’re not going to change that now are we?

Ìý

McCartney

What we have to do is at least acknowledge the uncertainty and at least say I’m not sure more often.Ìý And I think one of the problems that we have in medicine is that we’re not very good at saying actually I don’t know.Ìý And whenever you say you don’t know that’s a huge opportunity because what you can do then is you can acknowledge your uncertainty and you can work to reduce it.Ìý And that’s the hallmark I think of good science and I don’t think we’re very good at doing that particularly at public health interventions and particularly when it comes to diet.Ìý But there have been randomised control trials looking at certain diets like, for example, the Mediterranean diet, albeit mainly at people who are trying to prevent a second heart attack or a stroke in the main.

Ìý

Porter

Let’s go back to this saturated fat message though because that’s – I mean I’m 52 I was brought up on this message, as were most people, it’s never really been questioned, we were just told, and what we’re saying now is that the evidence for it was a little uncertain.Ìý I mean are you convinced by the evidence behind the link between saturated fats and coronary heart disease?

Ìý

Williams

I am convinced by it because, as Margaret has said, there are many intervention studies, smaller intervention studies, that have looked at diet, they don’t have the power, they’re hugely expensive those sorts of studies.Ìý The studies in the States, the low fat trial in the States in 50,000 women and those are the sorts of numbers we’re talking for what’s called a primary intervention trial, cost nearly a billion dollars with an avenue of follow up.Ìý But I have done studies, I’ve done studies in which I’ve substituted fats for other fats, I’ve done what I call supermarket studies where I’ve worked with supermarkets and we’ve changed the fats in ready meals and garlic breads and so on.Ìý When you do that, despite the fact these people are free living people, their cholesterol levels – their LDL cholesterol levels come down – now cholesterol is a very powerful surrogate bi-marker for heart disease.Ìý So we can extrapolate from those data.Ìý I’d love to have RCTs, we’re not going to have them…

Ìý

McCartney

Ah but there are huge problems when we start to use surrogate markers, because again and again surrogate markers are shown not to be very good when we finally do the really good studies that can show us finally whether or not our impact on cholesterol really does make a difference to whether or not you die or whether you have a heart attack or a stroke.

Ìý

Williams

But we can’t do that with…

Ìý

Porter

All we’re going to ever have is surrogate markers now, we’re not going to have a definitive trial…

Ìý

McCartney

Well I think that’s a really bad thing to aim for, I think either we say we’re not very sure about what’s going on here, this is what our best guess given the data available or we say actually we want to do this really properly and we do invest the time and money and effort and energy.

Ìý

Williams

I would love to make such a trial happen.Ìý I’ve actually started talking 10 years ago about such a thing.Ìý In the end this is 40 years old.Ìý When I was an undergraduate studying nutrition it was the fat versus sugar, it’s not fat versus sugar, it is fat and sugar and it is the fact we’re not eating fruit and vegetables and it is the fact we’re not eating dietary fibre.Ìý So the intervention study we really want is an intervention study of a whole healthy diet, not one only about one component.

Ìý

Sculthorpe

I think the polarisation that is fat, is it sugar debate it’s actually confused people more than it’s helped.Ìý So if you say you’re supposed to cut down sugar and you’re supposed to cut down fat well there’s not a lot left.Ìý And so people don’t really know what to do and that’s one of the issues is there’s kind of mixed messages in terms of what’s the best way forward.

Ìý

Porter

Christine this is a problem with the current polarisation – fats are bad, fats are good, sugar’s bad, sugar’s good – well not many people are saying sugar’s good at the moment.Ìý But it seems that we can only deal with one potential hazard in our diet at the moment and if the evidence for the saturated fats argument is shaky, let’s say, that just pushes it more towards the carbohydrate.

Ìý

Williams

I don’t know why it does but it seems to.Ìý I mean for example one of the reasons we’re not so worried about saturated fat now is our saturated fat has fallen from 55 grams a day down to 32 grams a day, probably most people in the UK, those ones who are at greatest risk, have reduced their risk, that’s one of the big things, we can’t study it now because there aren’t enough people.Ìý We were eating 130 grams of fat a day in the 1970s, heart disease rates have halved in that time, in the time that saturated fat has come down.Ìý In many ways you could say we’ve had the experiment.Ìý So sugar, I’m concerned about sugar but there’s no RCT evidence about sugar, there’s no RCT evidence that it causes heart disease, none whatsoever.Ìý There’s no evidence that fruit and vegetables are protective against heart disease, if you want randomised controlled data that is the whole point, these studies are incredibly difficult to do.Ìý We have real life studies – Finland reduced its rates of heart disease by ferociously intervening in relation to diet.Ìý There are islands that have changed their whole fat supplies – Costa Rica, the heart disease rates have come down.Ìý They have in the UK, we have a living experiment.Ìý As a scientist I’m not happy with it but it is the best we’ve got.

Ìý

Sculthorpe

There’s a slight contradiction in the experiment though I think which is that we’ve got this reduction in the dietary fat that we’ve had a reduction in coronary heart disease deaths but within the same time period we’ve, by a factor of 10, increased the number of obese individuals that we have…

Ìý

Williams

Absolutely.

Ìý

Sculthorpe

And none of that quite marries up.

Ìý

Porter

But Nick it’s an interesting observation that heart disease has halved, our intake of saturated fat over the same period has dropped dramatically, despite the fact that as a nation we’re always being criticised for becoming more sedentary and our waistlines have got bigger and bigger.Ìý You would have expected heart disease to have gone the other way, does that not show that cutting back on saturated fat has had some benefit for the public health?

Ìý

Sculthorpe

I think it could be interpreted that way.Ìý I think it’s a little dangerous to ascribe all of the benefits of changes we’ve seen over the last 20 years to one particular root.Ìý I would probably also argue – I originally trained as an exercise scientist so I would – that people are probably more aware of how much exercise they should take, there are fewer smokers than we’ve ever had before and all these things feed into that.Ìý We’re probably better as well at treating the individuals who’ve got coronary heart disease in the first place.

Ìý

Porter

Margaret McCartney, as an observer on the public discussion in this arena, do you think people from both sides cherry pick the data?

Ìý

McCartney

Yeah I think there’s a really good point in that and it is a real shame there’s been so much polarity in the press but I think actually….. there is actually quite a lot of areas to agree on.Ìý And I think that probably what people can agree on is that moderation does seem to be a good thing, a Mediterranean style diet does seem to be better than what else we have to offer.Ìý But there is still kind of a lot of uncertainty.Ìý It would be much better I think if we just all kind of confessed what we don’t know, made plain what we do know and really try and get rid of as much of the fad diet industry as possible.

Ìý

Porter

Margaret McCartney, Nick Sculthorpe and Christine Williams thank you very much.

Ìý

It is not the first time that we have covered this subject, and I doubt it will be the last. But whatever the facts, it is vital that new research is reported accurately.Ìý Another aspect of this debate that concerned us here at Inside Health were reports that Sweden has recently reversed its nutritional guidance on dietary fats in light of similar unease about the strength of the evidence. ÌýBut, once again, the truth is somewhat different, as we discovered when we spoke to Anna Karin Lindroos from the Swedish National Food Agency.

Ìý

Lindroos

It’s not true that it’s okay to eat saturated fat now in Sweden.Ìý Those rumours are based on discussions in blogs and I’ve heard from it from abroad but not in Sweden directly.Ìý The Swedish recommendation on saturated fat intake is based on the Nordic nutrition recommendations that were published in 2012.Ìý It’s a very strong recommendation that saturated fat intake should be limited to below 10% of the total energy and that’s the same level as all the Nordic countries and also other European countries.Ìý And it’s not a new recommendation, it’s been recommended for a long time to limit the saturated fat intake.Ìý

Ìý

Porter

Anna Karin Lindroos putting the record straight.Ìý And the rumour that the Swedish authorities now think it is okay to eat more saturated fats seems to have originated from a report looking at diets in obese people, but the findings were never meant to apply to the rest of the population.

Ìý

If there is a confusing issue that you think we should look into then please do get in touch. You can tweet me @drmarkporter or email insidehealth@bbc.co.uk.

Ìý

Dave contacted us to ask what doctors look for when they assess a mole. He is in his late 40s and has dozens of them. Well Dave it often starts with the alphabet and ABCD and E.

Ìý

Julie Newton Bishop is Professor of Dermatology at the University of Leeds.

Ìý

Bishop

A is for asymmetry. ÌýB is for border irregularity – so the edges might be notched, uneven or blurred.Ìý C is for colour – so they might have pinks, reds, whites, greys and blacks, as well as the more usual brown.Ìý D is for diameter – bigger usually than about six millimetres.Ìý And E is the one which is variably represented in different systems but I think E for evolution is a very useful concept.Ìý There are some very funny looking moles about but if they’ve always looked like that then of course that’s very reassuring, a mole which is changing, growing progressively, changing in all those criteria – ABCD – that’s the one we’re looking for.

Ìý

Porter

So what would happen if somebody did have a lot of moles, I refer them to somebody like you, you have a look, do you have a look at each individual mole on their body?

Ìý

Bishop

Actually what we do is we stand back, we see what sort of moles this person has and how they’re distributed and we look for ones that stand out from the crowd to really focus on.Ìý So we’re looking for the bigger ones, the darker ones, that ones that are more irregular in shape and particularly if they have irregularity in colour and then we home in on those, we have a good close up look with a naked eye and then in clinic we’re able to look with a magnifying device called a dermatoscope.

Ìý

Porter

One of the problems of course for people with lots of moles is they might come and see somebody like you, be given the all clear, but that’s a snapshot in time isn’t it, what about follow up, how do you make sure that there isn’t subsequent change because you can’t be seeing these people every six months forever?

Ìý

Bishop

First of all we’d ask about family history because risk is higher if you have a family history.Ìý If we consider them to have an abnormal number of moles, something we call the atypical mole syndrome, our mission is to teach them how to look after their moles in the long term.Ìý And particularly where there are lots of moles on the back we like to teach their partner how to look after the moles too.Ìý And we have a website which attempts to teach people what changes in moles are okay or normal and what are not.Ìý How to know their own moles and keep an eye for the rest of their life.

Ìý

Porter

Can you give me some idea of the timescale involved in a mole going from being an innocent mole to one that might be life threatening – are we talking weeks, months or years?

Ìý

Bishop

Well the commonest melanoma is a superficial spreading melanoma and we think that has a relatively slow growth rate.Ìý So it may be many months, if not years, in the production as it were and it’s that sort of melanoma that the ABCDE rule is aimed at – the slow progressive change in shape or colour.Ìý And the good thing is that it is the most common because it means you’ve got time to spot one.

Ìý

Porter

And what about the ugly duckling rule that the Americans use?

Ìý

Bishop

I think this is particularly helpful for the less common form of melanoma – the nodular melanoma – where actually the lesion may be symmetrical and just one colour and would fail the ABCDE test.Ìý But it would look different to everything else and that’s what the ugly duckling rule is about, it’s saying have a look in the mirror, your partner can help with your back, and look to see what your moles or other things on your skin look like and say to yourself is there something that’s different here, is there something that’s either a different colour or a different size and show it to your doctor, particularly if it’s changing.Ìý And indeed I think that taking baseline photographs on your iPad or something like that or your tablet where you can have a good look at it and zoom in on the mole, I think that is a very useful thing to compare your moles with in the future because of course we forget.Ìý So in the future you might think well that mole looks a little odd and if you have a photograph to go back to you might find it looks just the same or if it had changed yes that would be a very strong indication to go to your doctor as quickly as you can.

Ìý

Porter

Professor Julie Newton Bishop. And if you visit our website you will find a link to a pictorial guide of what to look for when checking your moles.

Ìý

Big companies are always coming up with new ways to attract the best employees but the latest corporate carrot on offer – egg freezing – got us wondering here at Inside Health. Apple and Facebook are reported to be offering to pay for female employees to freeze their eggs in order to attract more women. But is that really what is behind the rise in private clinics offering this type of service? Are ambitious career driven women putting starting a family on hold so they can get further up the corporate tree? And what might be involved if you were to take Apple or Facebook up on their offer?

Ìý

Professor Sjoerd Repping is Chair of the Centre for Reproductive Medicine at the University of Amsterdam.

Ìý

Repping

So we first started doing this in 2011, after having initiated egg freezing four or five years before that already for medical reasons.Ìý

Ìý

Porter

And looking at the women that you’re helping what sort of reasons do they give for coming to your clinic?

Ìý

Repping

Yeah right, so that’s actually a very interesting discussion because in the majority of the discussions in public people would say that these are women that are postponing child bearing because of their career.Ìý While in fact if you talk to these women that come to us for freezing their oocytes it’s mainly because they have the desire to have a family and in order to have a family they need only not a child but also a husband.Ìý So of course it’s very easy to get children without a man, just either – you know you go to a bar and you find somebody that gives you his sperm and then you can become pregnant, you can also order sperm online.Ìý But these women do not only want to have a child they want to have a husband and a child.Ìý And since the husband isn’t there they figure that it might take some time to find this perfect man but during their quest for this perfect man time passes on and that decreases their chances of pregnancy.

Ìý

Porter

Because the perception in the media is that these are ambitious career women and that’s why they’re putting their families on hold but what’s practically involved?Ìý How, first of all, do you assess whether their fertility is an issue?

Ìý

Repping

Yes so the biggest assessment actually is age.Ìý So we do not freeze eggs for women under the age of 30 because if you’re 25 you still have five years of chances of pregnancy that will remain the same in those five years to come, so in that respect there’s no use in freezing your oocytes or your eggs when you’re 25.Ìý So we start doing this for social reasons when you are between the age of 30 and 40.

Ìý

Porter

I mean would you look at ovarian reserve as a factor in these women before you progress to collecting their eggs?

Ìý

Repping

Yes, so something that you see of course among these women that present to our clinic with the request to freeze their oocytes, there are women there that are potentially still relatively young, maybe 31, 32, that have maybe already have gone further in their ovarian age, so then actually that is a sort of discussion then if that situation is not a social reason to freeze your eggs but it could turn out to be a medical reason because you are entering menopause earlier.Ìý But the majority of these women have an ovarian reserve that fits their age, an ovarian reserve of course decreases with age and that the biggest assessment there is to determine age to look at the ovarian reserves by counting the number of follicles on your ovary and that sort of determines the amount of oocytes that you can collect to freeze.

Ìý

Porter

Ovarian reserve is the term used to describe the capacity of the ovaries to produce eggs – the greater the reserve the more likely a woman is to conceive and have a baby. It is based on two investigations – an ultrasound scan of the ovaries and a blood test to measure levels of a chemical called AMH.

Ìý

Peter Bowen Simpkins is Medical Director of the London Women’s Clinic.

Ìý

Simpkins

AMH is a hormone, it stands for anti-mullerian hormone and Muller was the man who first described that part of the embryo.Ìý It gives us an idea of how many eggs there are left in the basket, as it were.Ìý And we combine that with an ultrasound scan taken just at the beginning of the cycle which is called an antral follicle count and that looks at these little follicles around the edge of the ovary and you can count them and if they’re over a certain number we can say well you’ve got plenty of eggs there and if it matches up with the AMH you can say things are okay.Ìý You can’t say with the numbers well that gives you six and a half years or something like that, all you can say is you’ve got plenty of reserve.Ìý But plainly if you leave it a couple of years you’d have to repeat those tests.

Ìý

Porter

And how confident can we be in the results of that test, is it very accurate?

Ìý

Simpkins

No, it gives a generally good view.Ìý I mean there are plenty of women who’ve got pregnant with a low AMH, having said that their chances are much lower.Ìý The antral follicle count obviously shows you these little follicles round the outside of the ovary and they potentially are going to hold an egg.Ìý So if you see quite a lot of antral follicles that bodes well.

Ìý

Porter

So it gives the woman a snapshot at the time as to what her fertility is at the moment and what it’s likely to be in the near future?

Ìý

Simpkins

Yes, I mean there is another test which has been done for years called the follicle stimulating hormone and that’s a pretty accurate test for the cycle in which it is taken in but it doesn’t tell you anything about the future really, unless it’s very raised which suggests the woman’s entering the menopause.

Ìý

Porter

Peter Bowen Simpkins. But if a woman does decide to opt for egg freezing, there is a bit more to it than you might think.

Ìý

Repping

Yeah this is very important to address because it seems also sometimes in societal debates that you go to this clinic and you have a consultation and the same afternoon we freeze your oocytes and you’re done.Ìý It’s a rather intensive procedure, it’s very similar to doing an in vitro fertilisation procedure.Ìý So these women have to take hormonal injections for about two weeks to mature multiple oocytes in their ovaries and when those ovaries have allowed those oocytes to grow then there will be a pickup, as we call it, and this is done trans-vaginally where we retrieve the oocytes from the ovaries.Ìý At that point the oocytes are in the lab and the lab then freezes those oocytes.

Ìý

Porter

How long can they remain frozen for?

Ìý

Repping

Technically these eggs and oocytes can be kept in a frozen state indefinitely and we’ve done this in the past mainly for other tissues, so for instance freezing of sperm is already done for more than 50 years.Ìý The only issues that you have if there is a decrease in quality is not so much the length of the freezing but it’s the actual freezing and thawing.

Ìý

Porter

What happens then?Ìý So three years down the line the woman meets the man of her dreams, they get married and they want to start a family.Ìý What happens then – she comes back to the clinic and says I’ve found the man?

Ìý

Repping

Well hopefully if she’s found a man they become pregnant naturally, now if that doesn’t work potentially because your oocytes have become older, those that have remained in your body, then you could revert to the clinic and say now I would like to achieve a pregnancy with my frozen oocytes because those are more likely to give me a pregnancy than my fresh oocytes, so to say, that have aged for an additional three years.Ìý You thaw the oocytes, the woman doesn’t need to go on treatment at that point, you use the husband’s sperm to fertilise the oocytes, you generate embryos and those embryos then are transferred, mostly one at a time, and then hopefully those embryos will lead to a pregnancy.

Ìý

Porter

And success rates are what?

Ìý

Repping

So this is of course the most important question.Ìý What we know from egg freezing actually doesn’t always come from the situation that we’re talking about now – from social reasons – so eggs have been frozen for a very long time, until recently it was very unsuccessful.Ìý In the old days we used the method called slow freezing, eggs are exposed to a cryopreservation medium, sort of an antifreeze, and they are slowly cooled towards a temperature of about minus 200 degrees Celsius.Ìý That slow freezing works for most cells, it doesn’t work for oocytes as well.Ìý The real success actually came about 10 years ago. The major jump was made towards developing a new technique called vitrification, the media that we use for freezing is different and the duration of the freezing process goes from a couple of hours to a few milliseconds.

Ìý

Porter

So as a rough guide, if you were sitting opposite a woman, say she’s 35 when she donated the eggs, she’s come to see when she’s 38, what sort of success rates can you quote for her?

Ìý

Repping

What we say is that the chance of pregnancy would equal about the chances of pregnancy that a 35 year old woman would have when she was undergoing IVF.Ìý And for a 35 year old woman undergoing IVF the pregnancy chances are about 30%.Ìý So in that respect it’s successful but even still the general assumption sometimes is that if you’ve frozen your oocytes this means that you will surely get a child and this is absolutely not the situation.

Ìý

Porter

Professor Sjoerd Repping speaking to me from Amsterdam.

Ìý

Just time to tell you about next week when we will debating the benefits of standardised packaging for tobacco, what can we learn from experiences in Australia? And we would like to hear your views on topics we have covered so far for a feedback special at the end of the series. So please email your bouquets or brickbats to insidehealth@bbc.co.uk.

Ìý

ENDS

Broadcasts

  • Tue 3 Mar 2015 21:00
  • Wed 4 Mar 2015 15:30

Discover more health facts with The Open University

Can you detect health fact from fiction?

Podcast