What is considered mild male factor infertility?

Normally we assess the normality of sperm parameters on the basis of WHO criteria which tells us that the concentration of sperm should be 16 million per ml of the semen, the progressive motility should be more than 30 percent or the total motility should be more than 40 percent and the normal shaped sperm should be 4 percent or more to have a chance of natural conception. If one or more than one parameters are slightly below these cut off levels, we could consider and label it as mild male factor infertility. Although there is no clear cut levels or categorisation of mild moderated severe but it could help in planning the treatment because if everything in the female is fine and it is the only reason for difficulties in conceiving, you could plan a different treatment than IVF, possibly you could try insemination rather than IVF directly. But if it is more than mild male factor infertility, you could try going through a more invasive or advanced treatment which could be IVF, ICSI, so it is important on that basis only.

Normally, when we have a sperm that is according to the WHO criteria close or little bit below the reference values, the set reference values, we tend to describe this man as a man suffering from mild infertility. The frequency is quite often. I do not have the numbers but it’s quite often and we have no data describing the prevalence of mild infertility, male infertility but I would say that it’s quite often and it’s quite challenging because it’s the group of men that it’s not clear whether they will need or not a form of assist reproduction and it’s not clear for how long we should allow them to try on their own before recommending them to move on to an a form of assisted reproduction. Obviously, a man suffering from mild male infertility has good chances for a pregnancy and natural conception as long as the female partner has no other factors that may affect the overall fertility of the couple. So my advice would be for these couples to ask the opinion of an expert before deciding to prolong their time of attempting for a baby via sexual intercourse.

These are difficult terms and it’s probably not a term that clinicians nowadays would really use. So basically what we would say is, if your sperm quality is normal, then it’s normal and if it’s slightly below normal, then it’s a male factor per se but perhaps if the sperm parameters aren’t quite normal, it doesn’t mean you won’t conceive naturally – it might take a little bit longer but doesn’t mean that there’s no hope. So it’s a difficult one really. Again, severe male factor is a subjective term. Some people might take it as less than five million per ml at that kind of level especially if the sperm isn’t moving well, there’s a lowest chance of conceiving naturally and a greater requirement for IVF treatment but mild male factor is difficult to say really.

Male factor infertility is a loosely defined entity, it’s supposed to be present in 50% of infertile couples. We have a working definition which is that one sperm parameter is abnormal, in other words below the 5% or when the total number of motile spermatozoa are about 10 to 20 million per ml. So let us say that the easiest definition is that one parameter of the sperm analysis is abnormal leads us to mild male factor infertility. These patients – if they fail to become pregnant after 24 months of attempts, then they usually need to proceed with more sophisticated treatments such as IVF. This mild male factor in infertility has to be contrasted to what we call severe male factor infertility whereby the number of motile spermatozoa is less than 5 million per ml. This is how we define these entities.