Low Sperm Motility
What Does Low Sperm Motility Mean?
Motility is defined as "the capability of movement", and therefore low sperm motility would mean sperm cells experience difficulty in moving from one place to another. Usually when a man has a fertility problem, it is either due to a low sperm count or an abnormality in many or most sperm cells. Low sperm motility can also cause a fertility problem simply because the sperm cells, for whatever reason, are having difficulty in traveling towards and finding an egg to fertilize.
Sperm And The Drunkard's Walk - Following ejaculation, one might think that the sperm cells all race madly towards the Fallopian tubes and the egg, the first one there winning the prize. Consider the fact that there are millions of sperm cells in the race, and the egg isn't always fertilized. This indicates the chance of any one sperm cell finding the egg is really quite remote. What actually happens is, rather than going in the same direction, sperm travel in all different directions, with roughly half of them going in the right general direction. An individual sperm cell will follow a path somewhat similar to the Drunkard's walk, familiar to mathematicians and statisticians. The Drunkard's walk is a random walk or path, where given the number of choices the drunkard (in this case the sperm cell) will have to make, the chances of arriving at the target location can be calculated. As mentioned before, the chance for a given sperm cell arriving at the right place is very low but finite, with the chance that one of the millions of sperm cells will reach the target (the egg) being much higher. Sperm cells in other words aren't equipment with GPS or any instinctive tools to tell them which direction to go and what decisions to make along the way.
Low sperm motility simply means the sperm cells just aren't able to do a very good job of swimming to where they should be going, or simply swimming too slowly in a situation where time does matter. Sperm that move in the right direction and move at an appropriate speed are referred to as motile sperm. For a man to be able to conceive, sperm motility of 50% or greater is considered about normal.
Causes Of Low Sperm Motility - What are some of the things that can cause low sperm motility? One of the more common causes of low sperm motility is if the man has a varicose enlargement in the veins of the spermatic cord, called a varicocele, which exposes the sperm to abnormally high temperatures, affecting their ability to travel. Sperm motility can also be negatively impacted by overly prolonged sexual activity, an infection, or a genetic cause. Sometimes surgery may be necessary to remove a varicocele, otherwise medications may be taken to improve sperm motility, or sperm injections and In Vitro Fertilization may be a possible solution.
Motility Measured By Examination - Fertility problems in men are most often thought to result form a low sperm count, and in most cases this is true. However, a significant percentage of fertility issues can be traced to low sperm motility. Where sperm count is measured by examining a sample of semen under a microscope, and calculating the number of sperm present in a unit volume, measuring sperm motility is only slightly more complicated in that the percentage of sperm moving in the right direction at a normal rate is what is to be determined. If 50% are going the right direction at a decent rate of speed, sperm motility is not considered an issue. If low motility is the case, the next step is to determine the causative factor or factors so treatment can commence.