What is Assisted Conception

Emma Howard: Here at the Baby Channel we are proud of the huge array of doctors and midwives that we have on hand to deal with your medical queries. Today Dr. Alison Taylor, a Consultant Gynecologist from The Lister Hospital, is here to talk about assisted conception. Hello! Thanks very much for coming in. Well, first of all, tell me what is assisted conception? Dr. Alison Taylor: Assisted conception covers a whole range of different treatment options for people that are having difficulty getting pregnant, and all of them are designed to try and obviously enhance the chance of pregnancy, and in general what they do is they tend to bring the sperm and egg close together, to a greater or a lesser extent. For example, they include things like intrauterine insemination, where you actually place the sperm sample into the uterus, and often combine it with some stimulation of the ovaries to make sure there’s at least one egg available. Emma Howard: This doesn't all have to take place outside of your body? Dr. Alison Taylor: No, not necessarily. So that’s the sort of simpler end of the spectrum, and then there are more complex treatments, like in vitro fertilization or IVF, where you are literally placing the egg and sperm together in a dish, in the laboratory, to encourage fertilization to occur, and then putting embryos back. But it also encompasses some other treatments for couples where there is perhaps no sperm or no eggs available, so things like donor insemination and egg donation as well. Emma Howard: So it’s all of it really, anything that doesn’t naturally occur, that you need any kind of help with becomes assisted conception. Dr. Alison Taylor: Yes really, although there are some things, like treating ovulation problems, perhaps doing tubal surgery, that we wouldn’t generally class as assisted conception techniques. Emma Howard: But they could have the same result? Dr. Alison Taylor: Yes, they are all with the same aim at the end of the day. Emma Howard: And what would you say of the indications for the different types of treatment, how would you know which route you need to go down? Dr. Alison Taylor: Well, it really should start once you have actually had some investigations, which we have talked about previously, and then you sit down with the couple and try and work out what’s the best plan of treatment for them as a couple, looking at where the specific problems arise. Things like intrauterine insemination, which is a very simple type of treatment, and generally really used for couples where there aren’t any obvious reasons found for a delay in them achieving a pregnancy, whereas IVF started off being used for women that had badly damaged tubes, as a way of overcoming the tubal blockage. Emma Howard: You just bypass the problem. Dr. Alison Taylor: Exactly, completely bypassing the bit that takes place in the tube, which is the fertilization of the egg and the early embryo development. You are taking that out of the body, doing it in the lab, and then going back to the uterus for the bit where implantation would occur. Emma Howard: If that’s the case, would you then put two embryos back in, or would you just put one? Dr. Alison Taylor: More commonly, we put more than one embryo back. In this country, in women under 40, we are not allowed to put back more than two embryos, whereas in women who are 40 and over, we can put back up to three embryos. But there’s quite a big concern now about the risk of multiple pregnancy, not only twin pregnancy, but particularly triplet pregnancies, so we try very hard to minimize that risk. Emma Howard: Just because you got it better it, so triplets can be more likely now, can't they? Dr. Alison Taylor: Yes, they would be, particularly in younger patients. If you are putting back good quality embryos, then yes, that risk becomes really significant. Emma Howard: And that’s an awful lot to think about, isn't it, from wanting one baby, to having three? Dr. Alison Taylor: Absolutely! But probably, more importantly, and some patients think if they get twins or triplets, well, it’s great, because actually you have got two or three for the price of one, and considering a lot of them are having to pay for treatment, then they perhaps think that that’s a pretty good deal. But actually, because of the complications with multiple pregnancies, it can be difficult, and they actually may end up not having live children at all. They may have babies that are lost in miscarriage, or babies that have died because they are severely premature, or they may have survived but actually have significant health problems and long-term developmental problems. Emma Howard: So it puts a huge pressure on the whole process? Dr. Alison Taylor: Absolutely! And on the family that’s then left dealing with all the problems long-term. Emma Howard: Yes, the emotional trauma of that. Dr. Alison Taylor: Yeah. But just coming back to the IVF, sort of indications for IVF. It started off being a treatment designed to overcome tubal problems, but now it’s commonly used to treat a whole host of different fertility problems, and not least of which are male factor problems, so problems with sperm counts. It's really one of the most practical ways of getting around that difficulty. Emma Howard: How would you describe the IVF cycle, I mean quite simply what happens? Dr. Alison Taylor: Well, it’s made up of a number of different steps during a treatment cycle, and the first bit usually involves some drug stimulation of the woman’s ovaries, to try and deliberately get her to produce several eggs in the one treatment cycle. In an actual cycle we will usually produce one egg per cycle, sometimes more than one, but usually one. In an IVF cycle we deliberately stimulate the ovaries to try and get several eggs to grow altogether, and grow to maturity. And then when we have got several eggs growing, we monitor them using ultrasound scans and blood tests. And then next step is to actually get those eggs out of the ovary in what's called an egg retrieval or egg collection procedure. Emma Howard: And the woman could be awake for this procedure? Dr. Alison Taylor: Well, yes, they usually have some sedation. You can do it without. I mean, I have had the odd patient who has requested to have it without any sedation at all, but in general most patients would prefer to have sedation or like a general anesthetic for it. It’s not a long procedure. It normally takes about 15 to 20 minutes. It’s done vaginally now. It’s not involving any surgery on the tummy or the abdomen, and it’s all done from below, using an ultrasound scan. Emma Howard: And of course you recover from that so quickly, don't you? Dr. Alison Taylor: Yes, I mean people are often a bit uncomfortable, and aware that their ovaries are a bit sore afterwards for a few days, but nothing too terrible. Emma Howard: And it’s not the same as having an operation where you have been cut. Dr. Alison Taylor: No, not at all. So we actually guide a little fine needle into the ovary, where the eggs are developing, suck the fluid out of the follicles, these fluid filled sacs in the ovaries where eggs are developing, and the fluid comes along some tubing, intra-test tube, that’s a sort of a test tube baby name for where the treatment comes from. Emma Howard: I see. Dr. Alison Taylor: And then those tubes are then handed on to the laboratory staff, the embryologist, and they look at the fluid under the microscope to see whether or not there’s an egg there. That’s how we actually get the eggs into the laboratory and out of the ovaries. And then the next bit, which is common actually to pretty much all assisted conception techniques, is getting a sperm sample and preparing it. So we just take the neat sperm sample that’s produced by the man and put it in a test tube, and then spin it down, and put it through a special preparation, which will help to select out the sperms that are the most normal and are moving the best, because those are the ones that are going to have the best chance of fertilizing eggs normally. Emma Howard: And you said spin it down, what did you mean by that? Dr. Alison Taylor: It goes into a centrifuge, which literally does spin the tubes very, very fast, and it helps to get the best sperm into the bottom of the tube. And then you can discard the top bit of the tubal fluid, keep the very best ones, and then there’s more washing processes that go on to concentrate the best sperm to that. Basically a little droplet of that concentrated good sperm is then mixed together with the eggs and left in the incubator overnight at body temperature, to see whether or not the eggs will fertilize. Emma Howard: So that's nature going on there, isn't it, just in a different circumstance? Dr. Alison Taylor: Yes, but just in the sort of scientifically controlled environment, in the laboratory, to try and make it as similar as possible to what’s happening in the normal situation. Emma Howard: It's like you are leaving them alone together overnight, let's see what happens. Dr. Alison Taylor: Yes. And then the following morning we have to actually see whether anything has happened, and say the embryologist will have a look at the eggs and see how many of them have fertilized. We wouldn’t obviously expect all of them to fertilize. Sometimes you get all of them, sometimes you get none of them, but usually it’s about two-thirds to three-quarters of eggs will actually fertilize. And having started off with, hopefully, a reasonable number of eggs; the average number of eggs in a cycle would be 10-12 eggs, we would then, if we have got some fertilized, have a choice of fertilized eggs and embryos that are going to develop over the next few days, and it’s from those embryos that we would then try and select the best two usually to go back into the uterus. Emma Howard: Is it obvious to your scientific eye or is it not? Dr. Alison Taylor: It’s the embryologists in the lab that do that. It wouldn’t be me as a clinician. They will do that by looking at the way the embryos have developed over those few days that they are in the incubator. We know that embryo should develop at a particular rate, so when the fertilized egg, which is just one round cell, first of all, pinches into two cells. Emma Howard: Yes, it’s the dividing process. Dr. Alison Taylor: That’s right. And then by the sort of second day those two cells would have divided again, should have divided into four cells, and so on, and by the third day they should be sort of getting towards the eight cell stage. And many, many human embryos actually are quite slow in development and will begin to stop, they are not so capable of going on and making a pregnancy. So what you are looking for are the ones that are carrying on at the right rate of development, and also, as they are dividing, not just breaking down into lots of little pieces, which are called fragments, but keeping nice whole cells that look really regular and round. Emma Howard: Well, you have described that easily, it sounds as if it would be quite obvious which ones to take. Dr. Alison Taylor: Sometimes it is, and sometimes it’s less easy to tell, because you can also have the most beautiful looking embryo which you put back and doesn’t necessarily make a pregnancy. So it’s not always guaranteed. Emma Howard: And you can’t control the whole process, a huge guiding hand. Dr. Alison Taylor: No. Emma Howard: One of the questions that we have got in this is that, I have heard embryos can be frozen, but doesn’t this mean the embryos can be damaged? Dr. Alison Taylor: Well, it is certainly quite an insult to such a tiny delicate structure, because we have got to remember that we are talking about embryos that are about a 10th of a millimeter in diameter that we are handling, and to freeze them is really quite a big insult to them, yes. And some embryos certainly won't survive being frozen or thawed out. So in general most units will be quite selective about which embryos they freeze, and they need to be pretty good quality ones, top quality, standard reasonable chance of surviving freezing and thawing out. But if they do survive, then they will have a chance of making a pregnancy, and there’s certainly no evidence that if a pregnancy results after using frozen, thawed out embryos, there’s no increase in risk of abnormalities or anything like that, from those pregnancies that result. So it’s well worthwhile, if patients have a good number of good quality embryos, to freeze some, so that if they get pregnant in that cycle, great, that’s fantastic. Then they can come back later on and have perhaps number two from the frozen embryos, and they wouldn’t have to go through all the stimulation and everything. Or if it doesn’t work out with that first fresh attempt, then they can have another attempt with that transfer again, as you say, without going through all the stimulation and the invasive of egg collection. Emma Howard: Another viewer has written in and asked, what are the associated risks with assisted conception treatment? Dr. Alison Taylor: I think that’s a really important question, and it’s something that patients are often quite worried about. The main risk of the actual stimulation from the woman’s point of view is that some woman’s ovaries are very, very sensitive to the drugs and can produce very large number of eggs. So the average might be 10 or 12, some women will readily produce 30 almost. Emma Howard: Oh my God, that’s shocking! Dr. Alison Taylor: And their ovaries will go from being something that's sort of about three centimeters in length, to being like little footballs. That certainly is uncomfortable for them being that large. But probably more important than that is, the very high hormone levels that are associated with those very big ovaries means there is peculiar shifts in the body of fluid, and they can tend to collect a lot of fluid in their tummy and in their chest, in the really severe cases, and need admission to hospital. So it’s very important to monitor the cycle really carefully to try and reduce that risk as much as possible, and be cautious with the dose in women that are likely to respond a lot. Emma Howard: And of course people going down that road know that there will be bump a few times ahead, so I would have thought that they would be slightly prepared for it not to be as smooth going. Dr. Alison Taylor: I think it’s really important that when they go through treatment that they have time to sit down and hear about the things that can happen at different stages, because I always try and tell patients that it's like a sort of series of hurdles to get over. The first one is the stimulation, and getting that just right, with a mass number of eggs, not too few, not too many. Then will they get eggs out of the follicles that are there, because that doesn’t always happen. If they get eggs, will those eggs get fertilized, that’s the next sort of hurdle to get over. And then, will the embryos actually divide and develop appropriately, and get to the point of having a pregnancy. Emma Howard: Each stage is a challenge. Dr. Alison Taylor: There are lots of steps. Definitely. Emma Howard: And your hopes are raised. Dr. Alison Taylor: That’s why the patients will often describe it as like sort of a roller coaster, each of these hurdles to sort of get over. Emma Howard: Well, thank you for explaining some of how it works. I know that we are going to see you again, and you can answer some more questions. We often have a lot on this subject. Alison, thank you very much for making it so clear. Dr. Alison Taylor: Not at all, thank you.