What techniques can be applied to make sure best sperm is used for fertilisation?

Eliza Filipiak, MSc
IVF and Male Factor - Techniques for Choosing Best Sperm
From this video you will find out:
  • What techniques do embryologists use to select the best sperm for fertilization during ART procedures?
  • How do embryologists assist patients with azoospermia, and what is the role of TESE?
  • In what ways can the IVF procedure serve both therapeutic and diagnostic purposes for couples struggling with infertility?

Male factor - techniques for choosing best sperm in IVF

When we we consider infertility, there are both female and male problems and causes. This the truth that all scientific sources confirm. Additionally, sometimes the cause of infertility lies on both sides and other times it is unknown. So surely infertility is not only a female problem, as it was still believed not so long ago. Eliza Filipiak – embryologist, biologist, biotechnologist representing Salve Medica explains herewhat techniques can be used to make sure the best sperm is used for fertilisation.

She starts with listing all the diagnostic tools that are used for male infertility, such as general semen analysis, sperm antibodies test, hyaluronan binding assay (HBA), chromatin dispersion test or oxidative stress measurement. Apart from semen testing, it is also possible to diagnose infertility using genetic testing, hormonal testing or early embryo development observation.

Eliza Filipiak stresses that Assisted Reproductive technology (ART) can be used for different reasons. It is implemented to help patients have a baby when other treatment had failed or is simply impossible. Generally, the artificial fertilisation process should mimic nature as long as possible. However, in some cases, the interference with the fertilisation process is so significant (like e.g. in case of ICSI – Intracytoplasmic Sperm Injection) that it is unlikely to let nature decide.

In natural pregnancies, it is the ovum and sperm interaction that decides about choosing the best sperm. When artificial methods are used, this huge responsibility is in the embryologists’ hands. But how do embryologists know which sperm should be chosen for fertilisation? Eliza explains this complicated yet fascinating process.

First of all, embryologists may not always be correct in their thinking. However, they are employing some techniques to make it more correct. If they have the choice, they always choose the motile sperm. The decision on which sperm is the best may be additionally facilitated. Generally, embryologists use two techniques for choosing the best sperm. The first one is non-apoptotic sperm selection. Apoptosis is in other words, a planned cell death. Using a metaphor, it is our body that decides which cell are going to be ‘sent to death’. It refers to sperm as well. In the ejaculate, when the testis work correctly, we have millions of sperm every day. However, it is impossible that all of them work correctly. Some of them are simply used and that’s why they are sent for ‘apotheosis’. In ART, sometimes it is impossible to know which sperm is, literally speaking, on its way to apotheosis as it may look the same as the healthy sperm. Fortunately, nowadays embryologists have techniques to distinguish the two groups of sperm. For example, by the use of the magnetic separation they can get rid of apoptotic sperm and use the best one for ICSI.

Eliza Filipiak also explains the other technique which is called PICSI. Here the prefix ‘p’ stands for physiology. pICSI involves pre-selecting of sperm based on whether or not they bind to hyaluronan. If sperm is correct, it has a hyaluronic acid receptor. Hyaluronic acid is present in the cells surrounding the ovum ( the so-called granulosa cells or follicular cells) and the role of the sperm is to bind it. If a sperm has a hyaluronic acid receptor, it means it is correct in a lot of other ways as well: it’s mature, healthy and able to fertilise the egg. That’s why it is so important to choose the hyaluronic acid-binding sperm in order to assure the correct fertilisation by means of ICSI. Of course, this technique is not used with patients who are diagnosed as having 90% of correct sperm.

As Eliza says, embryologists can also help patients with azoospermia (no sperm count in their ejaculate). There are different causes of this condition. Sometimes testis do produce sperm but the vas deferens is obstructed and the sperm are not appearing in the ejaculate. Other times, the sperm is produced in the testis but unfortunately in a very small amount. In both these cases, embryologists can perform TESE (Testicular sperm extraction) which is a testicular puncture to get the sperm directly from the testis and use them for ICSI. However, the sperm released from testis are not motile. They’re getting the ability to move when they are maturing in the epididymis.

Eliza also gives some details on another sperm diagnostic tool which is the observation of early embryo development for the first 5 days after fertilisation (up to the stage of the blastocyst). On the basis of it, embryologists can choose the best embryo to transfer. The way every embryo develops is also influenced by the quality of the sperm used.

In conslusion, Eliza Filipiak admits that the IVF procedure has sometimes not only the therapeutic role. It can also be a diagnostic procedure. After the IVF cycle, embryologists know more about infertility problems a particular couple is struggling with. Sometimes the way from the first IVF to the final successful one is long. It happens that embryologists know the reason of infertility only after the whole in vitro procedure – but not beforehand.


- Questions and Answers

Are there genetic or ageing issues that hurt male fertility? Does family history matter?

Yes, of course there are. Answering the first part of this question: there are many genetic reasons for male infertility, for bad quality of sperm and semen. It’s not even possible to list them all now. Almost every month different scientific groups discover a new gene which is responsible for some type of infertility or sperm damage. So for sure, genetics is responsible for male infertility. But not only genetics. Sometimes also environmental factors are damaging sperm and causing problems with fertility, as well as ageing. It is generally known that a female becomes infertile when she enters the menopause period and a male can have babies till the end of his life. Of course it’s true but the research published nowadays shows that the male fertility also decreases with time and the age of a man. The research also shows that sperm accumulates the genetic mutation much faster than the ovum. We all know that when a female is older than 35, the risk of, for example, having a baby with Down syndrome is high. But it is also true for a man. Of course a man can have a baby when he’s 70 but then his chances are smaller and the risk for the baby is bigger. Answering the second question: does the family history matter? Yes, sometimes it does. This is also about genetics. Our genes come from our parents so if a father had problems with fertility, his son might have the same problems, too. It’s not always like this but it can happen for sure.

Is DNA sperm fragmentation really giving reliable answers if semen is ok?

From my point of view, yes it is. But we don’t treat patients only on the basis of results. If a patient has a bad DNA fragmentation but he conceives a baby, then it’s wonderful and everybody is happy. But if there is a problem with fertility and we have the DNA fragmentation test showing that there is about 50% of not fragmented sperm DNA, we can only assume that this might be the issue. Believe me, I have seen patients with poor results, not only relating to the sperm fragmentation, and from those results, we would say that the patient has a very big problem with fertility. And then after some weeks or months, this patient has a spontaneous pregnancy. So we don’t treat the result, we want to treat the problem which is not having a baby. The results are somehow helping us to find the reason but they are not the reason. I hope you understand what I mean. Sperm fragmentation is also not something that is given to these patients forever. It is caused by many factors, e.g. by the inflammation which can be treated or by some environmental factors, cancer, high temperature or lifestyle. So sometimes we cannot influence DNA fragmentation but other times we can influence it and cause less sperm to have fragmented DNA. So keep in mind that this is something we can help with before we start the IVF treatment.

We have had a donor cycle with donor eggs and my husband’s sperm. We were told the donor was very fertile. The result was 50% fertilisation with ICSI, 4 embryos in total. We think this is very poor for donor eggs. What could be the reason? Embryo quality on day 5: 1x 3aa, 1x 2aa and on day 6: 1 x 1aa and 1x 2ab. We have had 1 failed transfer, with the 3aa. Wondering if it is worth trying the lower quality embryos and why is the fertilisation so low?

I’m not able to answer this with 100% certainty. I think nobody is able to do it. I don’t know how many eggs were fertilised here that we had only 4 embryos in total. The reason can be in the sperm itself. Sometimes it might happen that not all the sperm chosen for ICSI was correct. Even if there some special techniques used, this is something we cannot help. Answering your question if it’s worth trying: I think it is. If you have embryos, it’s always worth trying. These are not only the best quality embryos that bring about pregnancy. Usually, we use the best quality embryos at the beginning, for the first cycle and the first transfer. When we don’t have the pregnancy, then we try with the second very good quality embryo. If then we still do not have the pregnancy, we try with the last very poor quality embryo and sometimes we have a pregnancy. So you never know. Of course, there is a matter of chance and risk, like always in fertility treatment. It’s more about the chances, it’s never about being sure. But I know that for a patient it is a 1 or 0 situation: either you are pregnant or you are not pregnant. We can say: statistically, you have 50% of chances to have a baby from this embryo and from the other only 30%. But these are only percentages. I know you’re interested in whether you can have a baby or you cannot. What I can only advise here is always keep trying. If you don’t try, you don’t have a baby. I’m sorry, but unfortunately, it works like this.

Is the tandem cycle in terms of semen possible? We are thinking of fertilising some of my eggs with my partner’s semen and rest with donor’s.

In our clinic it is possible but I don’t know if other clinics are performing such a cycle. But yes, it’s done sometimes. Especially if an embryologist thinks that maybe the semen is not perfect. For example, we see from previous cycles that we have very good eggs and we try to fertilise them with the partner ’s semen. We expect to have 80% of fertilisation rate as well as the embryo development but we end up with only 10% or nothing. So in such a case, we would recommend using the donor sperm for the next cycle or the third cycle. We can check both donor’s and partner’s semen and we can see which embryos develop better. There is the kind of a diagnostic procedure with which we know if this semen is useful or not. I have a short story which may show you what can happen sometimes. We had a couple some years ago. She had a lot of eggs and she was also the donor for other females. The receivers of her eggs were all pregnant but she was not getting pregnant with the semen of her husband. We did the first cycle, then we tried another. They wanted to fertilise all her eggs with the semen of the husband. But we decided to do this tandem cycle and try both donor’s and husband’s sperm. And at the end of the day, we had to transfer the embryo from the donor sperm because they developed and the embryos from her husband’s sperm did not develop. She got pregnant with this donor embryo and their child was born. And maybe a half a year afterwards, she called us to tell that she was pregnant with her husband naturally. So it happened although they tried for many years before the first cycle and although this semen was hopeless which we all saw. All the previous cycles with the husband’s sperm were not successful but after the first pregnancy and the live birth, they had the second spontaneous pregnancy. So they had the first baby from the donor sperm and the second baby from the husband’s sperm, both born and healthy. So you never know what could happen.

Do you think is best to start with ICSI right away (we are having mobility problem) or give it a try in a ‘natural’ way with IVF?

For sure it’s always better to try the natural way. In our clinic what we choose first is the IVF. But sometimes if we see the sperm motility is very poor, we would recommend ICSI. IVF can only be done if we have enough sperm and if they are motile. Sometimes the day the test analysis is performed, the semen is worse but on the day of the fertilisation, we have better sperm out of the blue. We can say that if we have better sperm concentration and motility, we can try IVF. In my opinion, if it is possible, IVF should be used. But if it’s not possible, then it’s better to use ICSI. But it has to be decided on a case-by-case basis.

Do you have experience with vasectomy reversal and using TESE or MESA material? Is it better to find motile sperm instead?

Of course, it is better to find motile sperm. This is not only a matter of being motile or not, but this is also the matter of being more mature. Generally, urologists, who perform vasectomy claim it can be reversed and there is no problem. We think that sometimes it can be reversed and a man can have babies without any help but usually vasectomy damages testis somehow. It’s not direct damage to the testis because of course they are not damaged during a vasectomy. However, the testis and the epithelium where the sperm is produced are damaged indirectly after the vasectomy when the fluid produced in their sperm is going back to the seminiferous tubules making pressure. That’s the way the vasectomy can interfere with sperm production. Everything depends on the particular man and the time that has passed from the vasectomy to the reversing vasectomy. Generally, if a vasectomised patient wants to have a baby, this, of course, has to be the patient’s decision on how to perform it. But if the reversing is possible, I would try that. If it’s not successful, we can try to get the sperm from epididymis first and then from the testis. For me, that’s the order according to which it should be planned.

Is that true that if a man is over 50, the risk of a schizophrenia in a baby increases? And what about other diseases?

I don’t know anything in particular about schizophrenia. Probably there was such a study performed at a time and if they proved that, then it might be possible. Generally, I would say that the risk of infertility and somehow the risk for the child is increasing with the female and male age. It’s not like every child born from a father who is 60 years old would be healthy. Basing on the scientific papers, the risk is surely higher when both the woman and the man are older.

How important is the male nutrition. What kind of food helps sperm quality? What do you think of supplements? Would you recommend vitamins and folic acid for the men or something else?

For sure the nutrition is important, not only for fertility but for general health. The topic of oxidative stress is very modern as the etiology of many illnesses and probably infertility as well. Generally, we have to fight with the oxidative stress to have better semen quality. This means we need to eat well. Men need to eat antioxidants, meaning vitamins. They should eat what they generally don’t like, so vegetables and fruit. They should not smoke because it also influences oxidative stress very much. What about the supplements? Of course, there are many supplements for male infertility. Do they help? I would say they help if the reason for infertility is the lack of something that these supplements contain. But if the problem is different, then eating vitamins, supplements or vegetables would not help because the problem is not the oxidative stress.

When it comes to sperm count, what is a ‘normal’ range?

There are two reference values. It’s the concentration, which, according to WHO in 2010, is 15 million per millilitre and there is also the second reference value, which is the number of sperm per ejaculate. According to the same guidelines, it is 39 million per ejaculate. It’s okay if one of these values is within the reference range. If you have smaller concentration, let’s say 10 million per millilitre, but you have 5 millilitres of semen, it means you have 15 million per ejaculate. It’s okay, this is a normal range. If you are below the reference value in one parameter or even in all parameters, it doesn’t mean that you are infertile. It may mean that your chances are lower but as long as you have one sperm, we say that a man can be fertile. The semen quality is not the same during the whole time, it’s influenced by many factors. You can be below the reference values one day and in two months, you can be above the reference values. So it’s not a stable parameter.

Does acupuncture help to improve the quality of a sperm? What is your opinion?

I don’t have this experience from our patients but I believe it may help. As in the case of many other illnesses where acupuncture has proven to have influence, I believe it can help in both male and female infertility, too. But I have no experience and I don’t know any scientific literature on this subject either.
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Picture of Eliza Filipiak, MSc

Eliza Filipiak, MSc

Eliza Filipiak is an embryologist, biologist, a biotechnologist at Salve Medica. She is a specialist in male infertility diagnosis and co-author of the Polish Society of Andrology Guidelines regarding semen evaluation. A member of the Polish Society of Andrology, Polish Society of Reproductive Medicine and Embryology. Attendee of ESHRE meetings for many years.
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