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The motility of sperm is equally important to know and gives us a gauge if the sperm can reach the egg to fertilize it. Specifically motility is whether the sperm is able to cross the area to where the egg is at once the seminal fluid is released.
Seminal fluid has a natural energy source to propel the sperm through the journey to the egg. This energy comes from a fructose based source within the fluid. Even though this energy is supplied in the seminal fluid it is up to the sperm's motility to reach the destination.
When looking at motility you are able to measure how mobile sperm is. This will let you know if your sperm is able to fertilize an egg. If the sperm falls below fifty percent motile then a man may have a low chance of fertilizing an egg or they may be infertile.
Motile is a broad term to explain what the sperm needs to do to be able to fertilize an egg. When thinking of being mobile the word may correlate with the simple act of moving. While this definition is true it is much more than that.
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Sperm must do more than move. The sperm must be able to move forward in a strong enough motion to cross a great distance. Without this forward motion the egg will not be any closer than before.
There is sperm that is able to wiggle its tail but it does not move from its spot. Some sperm are able to move in a zig-zagging motion. This motion will make it less likely that the sperm will reach its destination because it is not heading straight for it. The sperm that moves forward in a straight line with have a much higher chance of fertilizing an egg.
Since there are so many option of how a sperm can be mobile scientists have classified sperm into categories. These categories are determined by how the sperm moves and can help explain whether the sperm is likely to fertilize or not.
For infertile seminal fluid the sperm is classified as non-motile sperm. This means that sperm is not moving at all and cannot reach the egg. In this case if there are no other sperm present the man would not be able to conceive a child.
There is also non-progressive sperm. This sperm does move its tail but it does not move forward. The sperm appears to vibrate in place and cannot reach the egg. Zig-zagging sperm are able to move from their original position. They do not progress in the correct direction through. They often move in a zig-zag pattern, in a curving motion, or other directions that do not lead to an egg.
The sperm that is able to fertilize an egg are classified as forward moving sperm. This sperm is able to move or swim directly toward an egg. These sperm are moving in a swift strong motion and are likely to reach the egg to fertilize it.