The Comprehensive DIY Guide to Assessing Male Fertility at Home

You can see sperm at home with an inexpensive microscope (less than $200). This guide will walk you through what aspects of male fertility you can determine yourself, what kind of equipment you need, and how to do it.

This walkthrough is based on the extremely thorough Sperm Analysis Document that the World Health Organization put together.

There are many, many aspects of sperm vitality and health that contribute to fertility. This guide distills the easiest to perform and most valuable procedures in professional sperm analysis that you can do at home.

This guide will technically work for non-human sperm samples as well.

DISCLAIMER:

This guide should not be used to make family planning decisions, and is not a replacement for clinical evaluation.

What aspects of fertility can you see yourself with a microscope?

Estimate Sperm Count: Determining sperm count yourself to the same accuracy as a clinical evaluation is outside of reach for most people. However, there are methods to estimate what your sperm count is.
Approximate Sperm Motility & Vitality: Sperm motility is graded based on observing the percentage of moving sperm in the sample and assessing the amount of sperm clumping.
Investigate the Total Lack of Sperm after a Vasectomy: If you had a vasectomy in the past and are concerned that your tubes may have reformed, verifying a lack of sperm under the microscope can be reassuring.
Confirm the Success of a Vasectomy Reversal: If you have had a vasectomy procedure reversed, you can verify that you have sperm cells present in your ejaculate again.
Assess whether you need a full clinical evaluation: If you take a look at your semen under a microscope and can’t easily find sperm or find only dead sperm cells, you may want to consider getting an evaluation by a trained clinician. For fertile males using regular untreated semen, you will find sperm swimming around practically everywhere in the sample.

Who should observe their sperm at home?

Our customers seem to primarily fall into a couple of categories:

Those who are anxious about being infertile and have not yet been to a fertility clinic.
Those who have been having difficulties conceiving, and want to do an initial, personal investigation, before going to a clinic.
Those who have had a vasectomy in the past, were clinically confirmed to no longer be fertile, but are anxious that their tubes have reformed over the years.
Those who are just simply curious and want to explore and understand their bodies.

In all these cases, simply seeing their sperm under the microscope brings 90% of the value to most customers. Thankfully, it is VERY easy to see your own sperm at home provided you have the right equipment.

What kind of microscope setup do you need?

Sperm cells are nearly invisible. Phase contrast microscopes are the gold standard for sperm analysis laboratories. They work by converting small differences in refractive index into changes in light intensity. The problem with phase contrast microscopes is that they are expensive (starting around $5000) and only work well with a narrow range of microscope samples.

The great news is that you don’t need a phase contrast microscope to effectively view sperm! We came up with a microscopy technique that makes sperm visible for 1/25 of the price of a phase contrast microscope.

If you are interested in the technical explanation, keep reading, otherwise if you want to skip straight to what kind of microscopes you should buy for this, skip to the next section.

The fundamental problem with using visible light to image sperm is that their refractive index is very close to seminal fluid, therefore light passes through sperm without bending very much. By using a transmitted illumination source whose numerical aperture is as low as possible (light hits the sample at a straight on angle), you can see a small amount of the transmitted light get absorbed by the edges of the sperm cell where the light passes through the cell at a tangential angle. This is still an incredibly small amount of light absorption.

If you are using a standard eyepiece to view the sample, the low numerical aperture of illumination light will also cause floaters in your eye to become visible. The exact same reason why the low numerical aperture illumination makes normally invisible sperm visible, makes normally invisible cell debris in your eye suddenly visible. You now will see the shadows of your eye floaters and the shadows of the sperm overlayed simultaneously. Making it extremely difficult to see your sample.

The solution? Use a microscope camera. Camera sensors don’t have eye floaters, so this is no longer an issue, and, as an added bonus, the image processors inside most microscope cameras use edge detection algorithms that increase the contrast of otherwise very subtle edges.

This combination of components excel at visualizing low-contrast biological samples. Paired with the motion of the live sperm themselves, it is trivial to pick out what is a sperm cell and what is not.

Okay that’s great, but what microscope should you buy?

You have 2 options:

We made a Sperm Observation Microscope Kit that was purpose built for observing sperm and has everything you will need. You can check that out and purchase it here.

OR,

To build this kit yourself, you will need:

A compound biological microscope, with or without a condenser, with at least a 4x and 10x objective.
A microscope camera with good low light and low contrast imaging capabilities, with at least 720p and 24fps.
Standard microscope slides & cover slips.
A micropipette that can measure 20uL.
A small jar to collect your specimen.

See our buyers guide to purchasing a microscope from Amazon capable of observing sperm here.

Understanding Microscope Magnification for Viewing Sperm

A quick lesson on microscope magnification.

Total magnification of the microscope = magnification of the objective x magnification of the eyepiece

OR if you are using a camera as we recommend here:

Total magnification of the microscope = magnification of the objective x apparent magnification that the camera adds.

From now on, I will be only referring to magnification numbers for the magnification of the objective. Whether you use a 10x eyepiece or a 25x eyepiece, you will see the same amount of detail in the sample. The objectives are what are actually adding more resolving power, not the eyepieces or the camera, at least for the majority of cases.

4x objective: useful for focusing on the correct focal plane. You will barely be able to see sperm as moving sparkles
10x objective: the most useful for directly observing sperm. It gives the best combination of ease of use, and clearly being able to see sperm.
40x objective: good for seeing more detail in the sperm cell itself. Note that without advanced microscopy techniques such as staining or sample fixation it is difficult to image details in the sperm cell itself. It is worth seeing what things look like under a 40x objective, but is not practically useful for doing analysis
100x objective: practically useless in doing sperm analysis as we are doing here. The sperm will swim out of the field of view immediately and due to the optics of this setup, you do not actually resolve any additional details with a 100x objective than you do with a 10x objective.

Microscope Setup

If you are using our Sperm Observation Kit, we have kit-specific video setup instructions which you can find here.

Otherwise, here is general setup advice that will work for most microscopes:

Set your microscope up on a flat, sturdy table.
Hook up your microscope camera to either the trinocular port if it is a c-mount or other trinocular port style camera, OR, if it is an eyepiece camera like the camera in the Sperm Observation Kit, take the eyepiece out and slide the camera in its place.

Some eyepieces are held in with a tiny set screw in the eyepiece tube. On the Sperm Observation Kit you have to remove one of these set screws.

Connect your microscope camera to a pc (if USB) or a HDTV (if HDMI).

If you are using a USB microscope camera, your computer should recognize the camera just like a webcam. You can usually use the in-built camera apps. On Windows this is the ‘Camera’ app. On Mac it’s the ‘Photobooth’ app. If your computer has a built in webcam, you’ll need to look for a button that switches to a different camera.
If your computer doesn’t recognize the USB camera, you’ll need to download the manufacturer's drivers or use the program included with your camera. The Sperm Observation Kit’s USB camera is recognized by every Windows PC we’ve tested and was recognized by most Mac’s we used other than one old Macbook we tried.
If you are using an HDMI camera, your TV should recognize it immediately, you just need to switch input sources.

Turn on the Transmitted Light Illuminator. This is usually a switch on the back of the microscope. You can tell that the light is on by looking at the bottom light of the microscope. The Sperm Observation Kit has both a transmitted and reflected light illuminator.
Use an easy-to-image sample on a microscope slide to calibrate your setup.

Prepared microscope slides with an extremely thin stained sample are ideal for this. The Sperm Observation Kit includes a single prepared sample slide for this purpose.
If you are using your own setup and don’t want to purchase a prepped sample slide kit you can put a drop of milk, yogurt, or similar onto a microscope slide with a cover slip on top to use for calibration.
Once you are comfortable using microscope, you don’t need to use a calibration slide, it just makes it easier for beginners to confirm that they have everything set up correctly since the focal plane where the sperm will be located is not as easy to visualize as a colorful, clearly textured sample.

Close your microscope condenser aperture down to a pinhole.

If your microscope does not have a condenser, such as with the Sperm Observation Kit, you can skip this step. The lack of a condenser in the optical path is the equivalent of closing the condenser down to a pinhole.

Start with the lowest magnification objective (usually 4x) and rotate the coarse focus knob until your sample is in focus.
Move up to the next objective (usually 10x) and use the fine focus to bring the sample into focus.
Your microscope is now set up to observe sperm. After you prepare your microscope slide with sperm on it, you can swap it in place of the calibration slide and you’ll be in the correct focus plane to see sperm swimming around.

Semen Collection Procedures & Best Practices

Now that you have a microscope set up and ready to use, we’ll go over the basics of observing sperm.

Maintaining abstinence from ejaculation for 7 days will give the most accurate results. Peak sperm count in a sample of ejaculate happens at day 7. This is why when you get your sperm counted in a clinical setting you must follow this procedure. That being said, you should see plenty of sperm in a sample from a fertile male at any amount of abstinence.
Capture the entire ejaculate into a specimen jar or other container. The first portion of the ejaculate contains a disproportionate amount of the sperm cells themselves. If you are estimating your sperm count, having the entire ejaculate to use is necessary.
Leave your sample in the specimen jar at room temperature, or ideally, near body temperature for 30 - 60 minutes. Semen will initially appear viscous and as if it contains sticky strands. These are protein structures that can entrap sperm and interfere with mixing your sample. Semen also contains protease enzymes that naturally break down these protein matrix structures. After 30 – 60 minutes the semen will become significantly less viscous and will change from cloudy and opalescent to see-through and off white. It’s obvious when this change happens. It can happen as fast as 10 minutes.
Swirl your sample for 30 seconds to mix the ejaculate anytime before putting on a microscope slide. Sperm cells do not appear evenly throughout the ejaculate and can swim around. Swirling the sample mixes the sperm and makes any sample you take representative of average concentrations. Be aware that mixing your sample can kill or injure some percentage of sperm cells. This is accounted for in the WHO Sperm Analysis Document.
Place a semen sample on a microscope slide. Using a micropipette, drop a 20uL liquid semen sample onto the center of a microscope slide. Place a cover slip over the sample, trying not to entrap bubbles. I’ve found the best way to do this is to drop it flat over the sample.

Notes:

Some semen will stick to the micropipette tip. This is okay. The original 20uL recommendation accounts for this lost sample.

If you are just looking at the overall health, motility of sperm, or looking for the presence of sperm. You don’t need to be careful with the exact amount of sample on the microscope slide. You can use a eyedropper, regular pipette, or syringe. Target getting about half a drop onto the microscope slide.

The reason 20uL is used is because it creates a particular depth thickness of sample between the cover slip and microscope slide. It is enough room for sperm to swim around, for most of the sample to be close to within the microscope’s depth of field, and give a consistent volume for measurement.

Observing Sperm

Without moving the focus knob, swap the calibration slide with the sperm sample microscope slide. As long as you have properly cover slipped your sperm sample, the focus plane where the sperm swim around should be in focus.

If you don’t immediately see sperm or in-focus particles floating around there are a couple of things to check:

Move the microscope slide around in the X and Y directions. You may have gotten unlucky and just put the microscope slide in the exact spot where there was an air bubble trapped under the microscope slide
Move the fine focus knob up and down. Does different stuff start coming into focus? It is possible that the microscope stage got moved in swapping from the calibration slide or the sample that you used for calibration is actually at a slightly different focal plane (rare).

For a male of regular fertility, you should be able to find sperm swimming around at this point. In fact, you should be able to find sperm swimming around anywhere you look.
If you find some percentage of your sperm not moving around at all, that is okay! Some sperm get injured during the collection process and naturally come out of the body immotile. You can find more on sperm motility evaluation below.
You can switch to the 40x objective if you want to see closer structural details of the sperm, however, the 10x objective will be what you use for the at-home analysis procedures.

At-Home Analysis Procedures

Estimating Sperm Count

It is well accepted that total sperm count contributes to pregnancy rates and time to pregnancy.

Historical data suggests that men’s sperm counts have decreased in the last couple of decades. However, one proposed explanation is that the way sperm counts are done is just becoming more consistent and accurate between laboratories, not that there is any substantial difference in the actual sperm count. Ongoing research is needed to clarify this potential social misnomer.

The Elephant in the Room

It is very hard to create accurate sperm counts, even in a laboratory setting. There are many factors that contribute to the total number of sperm per ejaculation. As an example, the amount and total time of male arousal prior to ejaculation can greatly affect sperm count. There are also many potential sources of error in the procedure required to determine sperm count, such as lost ejaculate volume due to sticking onto container walls.

The way that sperm is counted in a laboratory is complicated. It involves diluting the semen, adding chemicals that fix sperm in place, and using special microscope slides that have microscopic channels and chambers where you do the actual sperm counting.

The method that we are showing here is significantly easier and can be performed at home. The tradeoff is that this is just an estimation.

You can find the estimation method on Page 36 of the Sperm Analysis Document.

Conducting a Sperm Count Estimate

Before you begin, make sure that you write down to total volume of your original ejaculate by using the measurement lines on the sample collection cup.

Prepare a microscope slide for observation using the methods described above in Semen Collection Procedures & Best Practices. Set the microscope up in accordance with the Observing Sperm section above.

Use the 10x objective on your microscope to scan across the entire coverslip as shown in the diagram in a zig zag pattern, moving from one still field to another.

1 Page 37, Fig. 2.7

Count the number of both moving and non-moving sperm. Note that it is okay to double count individual sperm that may have swam from an earlier field into your current one. This is balanced out by sperm that swam out of a field that you are about to observe.

NOTE: If you are unable to find any sperm by scanning the entirety of a single preparation, you are very likely to have an extremely low sperm count and should get a professional sperm count performed. (It is also possible that you have an improper microscope setup)

Interpreting Results

After you have a total sperm count from your 20uL sample, you can calculate the approximate overall sperm count by using the equation:

Concentration (sperm/ml) = N x Vol x factor

Where:

N = observed number of sperm
Vol = total ejaculate volume in mL
Factor = 50 since we used 20uL of fluid on the microscope slide.

Note that this estimation will likely be slightly low since we are using a less costly brightfield microscope in lieu of a professional phase contrast microscope. Therefore it is harder to see immotile sperm and you will undercount immotile sperm. In any case, this is just an approximation, so take your results with a huge grain of salt.

According to Table 8.3 on page 213 of the WHO Sperm Analysis Document, the sperm count range of ‘fertile’ men, is anywhere between 11 million/mL and 254 million/mL.

NOTE: There seems to be something off about the Sperm Count formula pulled directly off of the WHO document. From our calculations it would take 72hrs of counting sperm on a single microscope slide to achieve a normal sperm count result. This does not pass the sanity check and is obviously not correct. We are working to figure out why it gives odd results and find an alternative estimation method.

Sperm Motility & Vitality

Before you Begin

Assessment of Sperm Clumping

There are two types of sperm clumping.

Non-specific aggregation: Sperm sticking to immobile sperm, non-sperm debris, or mucus strands.
Sperm Agglutination: Motile Sperm that are stuck to other motile sperm. They will be wriggling around, attempting to move without success.

Both types of sperm clumping are not ideal and will negatively affect sperm motility and therefore fertility. Substantial amounts of either could be cause for getting a clinical evaluation. See fig. 2.1 and 2.2 below.

Assessing Sperm Motility

Perform this assessment at room temperature. Sperm motility is temperature dependent. Clinical analysis of sperm motility is performed at 37C using incubators and heated microscope stages. Therefore this test is just an approximation of the results of what you would see in a clinical setting.

The basic idea of this test is that you’ll move the microscope to random spots on the microscope slide and count how many sperm are moving, and how many are not moving. We will compare the percentages of motile vs non-motile later.

Avoid assessing areas <5mm from the edge of the coverslip since those areas can dry out.
Try not to assess an area that was previously assessed.
Avoid choosing areas based on how many sperm are there. It should be random.
Score a given area at a random instant. Do not wait for sperm to swim into the area to begin scoring.

The WHO document specifies counting 200 total sperm (includes motile and non-motile) PER fresh microscope slide preparation. They start with two and then do some math to compare results and then do more sample slides if the results are off. Since we are just doing an approximation, you can count less than that – just 100 total. Understand that if you would like to do more than this, your error will go down with an increased number per slide, and an increased number of slides.

Interpreting your Results

According to Table 8.3 on page 213 of the WHO Sperm Analysis Document, approximately 35% - 92% of ‘fertile’ men’s sperm are moving, while the remainder is immotile.

Assessing Sperm Vitality

The methods described in the WHO Sperm Analysis Document to determine sperm vitality are outside of the scope of what can be done at home. However, sperm vitality testing is not recommended if at least 40% of sperm cells are motile, because that is enough to access high vitality.

Presence or Lack of Sperm after a Vasectomy or Vasectomy Reversal

Before you Begin

Note that in a laboratory setting, semen samples are put through a centrifuge, drawing any individual sperm in the ejaculate to a single observable area under a microscope, giving significantly higher confidence in the test result than what we can do at home. That being said, if you find even a single sperm cell yourself, you should assume that there are more, and you should get a full clinical evaluation.

Since we are looking for the lack of sperm, doing this procedure at home can provide you with a false negative. We do not recommend that you make family planning decisions based on the results you get here.

Conducting a Presence of Sperm Analysis

Prepare a microscope slide for observation using the methods described above in Semen Collection Procedures & Best Practices.

Use the 10x objective on your microscope to scan across the entire coverslip as shown in the diagram in a zig zag pattern, moving from one still field to another.

2 Page 37, Fig. 2.7

Interpreting Results

If you do not find any sperm by doing this procedure, there is a low probability that any sperm exist in the overall ejaculate. (see page 66, table 2.13 for the confidence intervals of undetected sperm)

Conversely, if you find sperm with this procedure, there is a high probability that more sperm exist in the overall ejaculate.

Final Thoughts

We hope that you found this guide to be helpful. If you would like to learn more about our sperm observation kit you can see the product listing here. If you have any questions or feedback, feel free to contact us here. Thank you for reading!

Citations:
WHO laboratory manual for the examination and processing of human semen, sixth edition. Geneva: World Health Organization; 2021. Licence: CC BY-NC-SA 3.0 IGO.