Semen Analysis: Sperm Testing for Male Fertility
- Lucy Lines
- Jun 23, 2019
- 6 min read
Updated: May 12
So your doctor has suggested a semen analysis for fertility testing.
Many guys will find this very confronting, but it is actually one of the most important steps in finding out why you haven't been able to conceive as quickly as you had hoped.
In my more than 20 years as an embryologist and fertility educator, I learned early on that it’s often easier to treat male infertility than female infertility. Assessing the male's ability to produce sperm is therefore a step that should take place early in your fertility journey.
Why bother testing for male fertility?
There are two main ingredients to making a baby – sperm and eggs. Then they have to meet and join together (fertilise), and then the resulting embryo needs to be able to grow, develop, and implant, etc etc etc.... There are actually LOTS of steps in getting pregnant, and quite frankly it amazes me that there are people who conceive spontaneously without ever needing to know any of this stuff!
But if you don't have the right ingredients, well, this would be pretty devastating to discover months (or even years!) down the track. And if any of these ingredients are missing, then spending more months 'trying' (having unprotected sexual intercourse) is kind of a waste of time.
1 in 20 men in Australia experience some sort of infertility. Male infertility affects approximately 50% of infertility cases and it's the biggest single factor affecting a couple's chance of conceiving, after a woman's age.
So what exactly does a semen analysis analyse?
There is no easy and convenient way to ensure that a woman has viable eggs, or to know EXACTLY when they're ready for fertilisation. We can make some fairly educated guesses (see my post on egg quality for more details), but we can never be 100% sure.
But with sperm health, it's much easier. A simple, non-invasive semen collection and analysis can easily tell us all about:
Semen volume: In my experience, this is usually somewhere between 2 - 4mls. The World Health Organisation (WHO) says that a normal sample is between 1.5 - 7.6mls (but I have seen up to 12mls!!).
Sperm count: How many sperm are present in the semen sample (sperm actually only make up about 5% of the entire ejaculate). A normal sample should have more than 15 million sperm per ml in total.
Sperm motility: How quickly the sperm are swimming.
Progressive motility: If the sperm are swimming in a relatively straight line.
Sperm morphology: How 'normally' the sperm are shaped.
White blood cell count: The number of white blood cells present in the sperm (an abnormally high count can indicate infection, which may impact fertility).
I sometimes refer to a semen analysis as being a bit like taking a photograph at a car yard. We can't know from looking at the photo whether the car is actually going to be able to ‘make the distance’ from fertilisation to baby. But if there’s no car in the photo at all, or it’s missing crucial parts like wheels – well, it's kind of pointless planning the trip!
In other words, we can't be absolutely sure by looking at sperm if they're going to be able to fertilise an egg, but we CAN see whether they are there, and if there are 'enough' of them to be viable.
How is a semen analysis conducted?
A semen analysis can be done at 2 different kinds of labs – either a pathology lab or an andrology lab. Andrology labs specialise in analysing sperm. It’s all they do, so you’re much better off having this test done at an andrology lab if possible.
You can get an andrology lab semen analysis request form from your GP or fertility specialist. The lab will require you to make an appointment to make sure that they have a scientist ready to assess the sample within the appropriate time frame to ensure accurate results.
Here are the steps that are followed in a typical semen analysis:
Firstly, the andrologist (sperm scientist) looks at the volume of the ejaculate.
Next, they take a small droplet of the ejaculate and assess it under the microscope using a special counting chamber such as a Makler chamber (pictured). An experienced andrologist can count 4 aspects of the sperm sample at once using with a Makler chamber and a special type of clicker-counter by clicking on one of 4 buttons:
Rapid forward progression (progressive motility)
Forward progression (progressive motility)
Movement but no forward progression
No movement
The total motility should be more than 40% (sum of 1,2 and 3 above) and the progressive motility (sum of 1 and 2 above) should be more than 32%.
Finally, the scientist needs to assess the morphology or shape of the individual sperm.
Oddly enough, it’s quite normal for MOST of the sperm to be abnormally shaped – a result of 90% abnormal forms is not unusual.
Once the scientist has assessed all of these parameters (volume, concentration, motility and morphology) they can then calculate the total amount of sperm in the ejaculate that are likely to be able to fertilise an egg (normally shaped and with forward progression).
Factors that can affect test results
The results of a semen analysis can vary greatly depending on how the sample was collected and how soon after ejaculation it was assessed. Temperature and time have a detrimental effect, so producing the sample on-site, or making sure that it is delivered to the lab at the pre-arranged time is really important. Some lubricants can also affect results.
Semen parameters can be heavily influenced by the man's health. A bout of flu or a high body temperature can completely wipe out sperm production and it can take up to 3 months before sperm are seen again in the ejaculate. There are also a number of supplements and some lifestyle changes that have been proven to impact sperm quality.
Semen volume, sperm concentration and sperm motility can all be assessed by a computer in some labs, but the morphology assessment is done by a scientist looking down a microscope and documenting what they see – so if you want the most accurate result, you should have the analysis done by an experienced sperm scientist.
Other potential male fertility issues
Anti-sperm antibodies is another parameter that is worth having tested. Semen is an antigenic compound, which means that it can promote an immune response – especially in the man who made it.
A natural barrier exists between the testes and the rest of the body that prevents a man's blood from ever coming into contact with his sperm. But if this barrier is somehow damaged, then his body can form anti-sperm antibodies.
Then, when the sperm are joined with the rest of the contents of the semen, the man's body recognises it as antigenic and tries to attack it by sending out antibodies which cause the sperm to all coagulate or stick together. This makes it virtually impossible for them to swim and/or fertilise an egg.
An anti-sperm antibody test, also known as an immunobead test, can be performed on the semen sample at the same time as a routine semen analysis.
Another potential issue is sperm DNA fragmentation, which refers to damage to sperm cell DNA. Testing for DNA damage is not part of a standard semen analysis.
You can request a sperm DNA fragmentation test from your GP or fertility specialist but it’s quite expensive – and in my opinion, usually not worth the cost because the test results are often contradictory and inconclusive.
Many people wonder about the impact of testosterone on fertility, as testosterone is the most important of the male sex hormones and plays a key role in a man’s overall hormonal health. However, when it comes to fertility, whether the man has high, normal or low testosterone levels rarely has any effect on a couple’s ability to conceive.
(Having said that - using steroids HAS been shown to have negative effects on sperm production and should be discussed with your Dr!)
Measuring testosterone levels can be done as part of a standard blood test that you can request from your GP – you don’t need a specialist referral to get this checked out.
Final thoughts
The results of a semen analysis can be confronting, but the reality is that you only need one sperm to fertilise one egg in order to make a baby.
In couples where the semen parameters are particularly 'bad' (low sperm count, low motility, high abnormal forms), couples can still conceive naturally, but the woman's age also needs to be taken into account.
If she is still young, the preference might be to continue trying naturally for a bit longer and hope you hit the jackpot, but if she is over 35 or if the couple want to have more than one child, then your fertility specialist may move you more quickly to assisted reproductive technology (ART) options like IVF.
If you’ve had a semen analysis and would like to talk through the results and have some guidance making decisions for next steps – please get in touch!
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