Sperm viability is important especially to a couple that is having trouble conceiving a child. It is in a simplified definition viability is whether or not a person has sperm that is alive. While a typical male has seminal fluid that has a large amount of sperm not all of the sperm are viable or alive.
There are many factors that affect whether a sperm is viable. It does not stop at the simple fact of if the sperm is alive or dead. Fertility is much more complicated than if sperm is viable or not. A test for fertility is successful if a man's sperm comes back and is at least sixty percent viable.
To test if a man's sperm is viable doctors and scientists use a sample of seminal fluid. This seminal fluid is measured to see what sperm is alive and what is dead. A common way to test if the sperm is dead or alive is to use a dye in the sperm.
The non-viable sperm cells, the dead sperm cells, will absorb the dye. This is because these cells will not have a solid cellular membrane. This allows the dye to leak into the cell thus dying it. A sperm cell that is alive will have a solid cellular membrane. Which will protect the cell from absorbing the dye.
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Looking past whether sperm is alive or dead viability focuses on the sperm cells that are alive. These sperm cells must be healthy. Any sperm cells that are damaged can make it hard to conceive a child. The damage, or defects, could be a number of problems.
The sperm may have its DNA altered making it non-viable. If there any antibodies present that fight sperm it can make it difficult for the sperm to fertilize an egg. Other chemicals can affect sperm and make it impossible for the sperm to fertilize an egg.
Sperm must be viable and healthy to reach an egg. The vagina is an acidic environment and it will kill the sperm as it travels to fertilize the egg. If the seminal fluid is not viable or it has a low amount of viable sperm it will be improbable that the sperm will reach the egg before dying. If there are factors that have decreased sperm viability it is likely the man will have trouble conceiving a child.
Fertility must include factor more in depth than just sperm viability. Viability of sperm is important but the sperm must also be motile. If the sperm has low mobility it can be difficult for the sperm to reach an egg before it is killed by the hostile environment of the vagina.
Another aspect that is look at is the total sperm count. If a man has a high sperm count it can help to combat if his sperm has lower viability. It is the same if the sperm count is low. Even if they have viable sperm with a low sperm count it can still be difficult for the sperm to fertilize an egg.