There are many things that can cause unexplained infertility and sometimes we will never find out what the actual cause is. I guess the correct thing to do while investigating the cause of infertility is going in order. Do all the studies, blood works, tests, study all the possible factors and if that came out that everything is normal, is correct then, we go to IVF and see in IVF protocol we sort of realise that there was something going wrong while seeing the development of the embryo (oocyte quality). Sometimes we cannot point out that this is because of that particular thing. This happens because in almost 33 to 35% cases there is more than one thing – there is bit of here and bit there and this way we build diagnosis.
There is a whole range of candidate things that may be going wrong. There might be something fundamental about a woman’s eggs and certainly that could be the case as women get older, there are fewer eggs that are actually capable of making a pregnancy ultimately and therefore the chances are lower. If you begin to add age into it, then it changes the whole dynamic around that. But subtle things about eggs, there may be things about the way that eggs and sperm go together, it could be that there is a fertilisation problem, that there is bad sperm binding, the sperm does not penetrate and that they don’t do all the things they need to do in order to get into the egg and fertilise the egg and that can also be an egg issue. It may be that there are subtle things about the fallopian tubes, we put dye through tubes to demonstrate that they are not blocked, we can look at them to make sure there are no adhesions or endometriosis around them. But actually, that doesn’t necessarily exclude functional things that may be going on in tubes that we have no real understanding of or way of assessing.
There may be more subtle things about sperm and sperm function, there may be things about the endometrium and how it works, functions and allows implantation. There are a number of candidate things that could be going wrong but for which we don’t really have the greatest testing to now ascertain as a screening test as we would do for most fertility issues.
