Sperm Morphology – how do you shape up?

April 14, 2017

by Dr. Rob Downer, Clinical Embryologist

Sperm morphology or shape is one of the parameters that is assessed and measured during routine semen analysis. We’re all familiar with the typical shape of sperm cells, which are often referred to as ‘little tadpoles’. When we check the shape of the sperm in the laboratory using a microscope we’re looking for a nice symmetrical oval head, a thick neck and a tail with no bends or kinks, as well as some more detailed structures.

When it comes to making sperm, how do human males compare to other mammals?

Not great, the fact is that human males are pretty bad at making sperm when compared to some other mammals. When we examine the shape of human male sperm under the microscope we will see sperm with big heads, small heads, two heads, bent necks, among others, in almost every sample and we only expect approximately 10% of the sperm to have ‘normal’ shape. This means that, on average, 90% of the sperm a man produces have an ‘abnormal’ shape!

So what about cases where you’re told that your sperm morphology is low?

This means that less than 4% of the sperm have normal shape. When informed that their sperm morphology is low the most common question from men is ‘what can I do to make it better?’ Unfortunately, recent findings in studies performed in 2012 and 2015 concluded that there is no relationship between a man’s lifestyle and his sperm morphology. As a result, these studies recommend that time should not be wasted trying to improve sperm morphology by making changes to lifestyle.

In a separate study it was concluded that the most effective and efficient fertility treatment for males with low sperm morphology is the use of ICSI, or intracytoplasmic sperm injection, which is a type of IVF where a single sperm is injected straight into an egg for the purposes of fertilisation.

What’s the bottom line?

If you are undergoing fertility testing and you are informed that your sperm morphology is low, it’s likely that there is very little that you can do about it. The best advice is to not waste time trying to improve sperm morphology and to invest this time more wisely in fertility treatment that is most likely to work.

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