If you have been looking for a way to tell whether you are fertile, you have probably found the same kind of list over and over. Tiredness. Lower sex drive. Thinner facial hair. A change in how your semen looks.
And you have probably finished reading feeling no clearer than when you started, because every item on those lists could just as easily mean nothing at all.
There is a reason for that, and it is worth explaining properly. This article is longer than most, because we would rather you leave understanding how this actually works than leave with another list.
The short answer: there is usually nothing to notice
Male infertility rarely causes symptoms. Most men with a low sperm count, and even men with no sperm at all, feel completely normal. There is no reliable way to work this out from how you look or feel. A semen test is the only way to know.
Cleveland Clinic says this plainly: there are no obvious outward signs of unhealthy sperm, and a semen test is the only accurate way to find out.
We know that is not the answer you were hoping for. But it is worth knowing now rather than later, because a lot of men spend months waiting for a sign that was never going to come, and those months matter.
There is something reassuring in it too. If you feel completely fine, that does not mean you have missed a warning. For most men, there simply isn’t one to miss.
This article is for education only and is not medical advice. If something feels wrong, or you have been trying to conceive without success, please speak to a doctor.
Why you cannot feel it
To understand why this is invisible, it helps to know what your testicles are actually doing.
They have two jobs, and this is the part that clears up most of the confusion.
The first job is making testosterone. This is the hormone behind your sex drive, your energy levels, your erections, your muscle mass, your body hair. When people talk about “male hormones,” this is what they mean. It is produced by one specific group of cells.
The second job is making sperm. This happens somewhere else entirely, in a different set of structures, handled by different cells. It is a slow, continuous production line that runs in the background of your life without you having any awareness of it whatsoever.
These two systems sit millimetres apart inside the same organ. But they are separate. One can be running perfectly while the other has stopped.
That single fact explains almost everything about why male infertility is so hard to spot. Everything you can feel – desire, erections, energy, the physical experience of ejaculating, comes from the hormone side. None of it comes from the sperm side.
So a man can have a completely normal sex life, feel physically strong and well, notice nothing unusual at all, and have very few sperm. Or none.
There is also, quite simply, nothing to feel. Making fewer sperm does not hurt. Making slower sperm does not hurt. There are no nerve endings involved and nothing changes on the outside. This is not something a more attentive man would have picked up on.
Why sperm production is slow, and why that matters
One more thing worth knowing, because it explains a lot later on.
Making a single sperm cell takes your body around two and a half months from start to finish. There is a production line running constantly, and what arrives in a sample today was started roughly three months ago.
This has two consequences that will come up again.
The first is that your results reflect the past few months, not today. If you had a bad flu, a stressful period, or a course of medication twelve weeks ago, that can show up now.
The second is that results move. Sperm counts are not a fixed personal characteristic like your blood type. They shift over time, sometimes substantially, which is why a single test is never the whole story.
Why every list of “signs” says the same misleading things
Here is something that will save you a lot of confusion.
Look again at the typical list: low sex drive, tiredness, difficulty with erections, reduced facial or body hair, sometimes breast tissue development.
Those are not signs of a low sperm count. They are signs of low testosterone.
They belong to the hormone side of the equation, not the sperm side. And because low testosterone and low sperm count sometimes share an underlying cause, these symptoms end up on lists of “male infertility signs”, where they get read by worried men as a checklist for their sperm.
They are worth mentioning to a doctor. Low testosterone is a real thing and it does sometimes sit alongside a fertility problem. But plenty of men with almost no sperm have entirely normal testosterone, feel completely well, and would tick none of those boxes. And plenty of men with low testosterone have perfectly adequate sperm.
If you have been reading those lists and thinking “none of this applies to me, so I must be fine”. That reasoning does not hold. And if you have been thinking “some of this applies to me, so I must have a problem”. That does not hold either.
The few signs that genuinely are worth mentioning
Most men have nothing to notice. But a minority do, and it would not be honest to leave those out.
None of these mean you have a fertility problem. They mean these are things a doctor would want to know about.
A heavy or aching feeling in the scrotum
Sometimes described as feeling like a bag of worms. This can be a varicocele.
A varicocele is an enlarged vein in the scrotum, similar to a varicose vein in the leg. The blood does not drain away as efficiently as it should, and the pooling raises the temperature slightly around the testicle. Sperm production is unusually sensitive to temperature, which is why this matters.
It is worth knowing about for two reasons. It is common, found in a meaningful proportion of men generally, and considerably more often in men having difficulty conceiving. And it is often treatable.
The catch is that most varicoceles cause no discomfort at all. Feeling nothing does not rule one out. They are usually found by a doctor during a physical examination, which is one of several reasons that examination is worth having.
Testicles that feel small or soft
There is a genuine relationship here. Most of the volume of a testicle is the sperm-producing machinery, so size does broadly track with production capacity.
But please do not try to assess this at home. Doctors measure it with a proper tool or a scan, and, importantly, they read it alongside hormone results and a semen test rather than on its own. Size alone tells you very little. What it does is help a doctor understand why a result came back the way it did.
We are deliberately not giving you numbers or a method here. Self-measuring produces anxiety, not answers.
Very little or no fluid when you ejaculate
This is one of the few things you might genuinely notice yourself, and it is specific enough to be worth raising.
A markedly reduced amount can suggest a blockage somewhere along the route, or that semen is travelling backwards into the bladder rather than out. The second of those is more common than people expect and has a range of causes, including certain medications and some surgeries.
Both are things a doctor can investigate, and some are straightforward to address.
Pain, swelling or a lump
This one is different from everything else on this page.
Please see a doctor soon, whatever your fertility plans are. A lump or swelling in the testicle needs assessing for reasons that have nothing to do with conceiving. This is not one to sit on.
Your history tells you far more than your body does
This is probably the most useful section of this article, and the one most likely to actually apply to you.
The things that most reliably point towards a fertility problem are not symptoms at all. They are events, often from years or decades ago, which produced no lasting sensation and which most men have long since stopped thinking about.
It is worth genuinely thinking back through these.
An undescended testicle as a child. Even if it was corrected, and even if it was corrected early, it is relevant information. The developing testicle is temperature-sensitive, and time spent in the wrong place can affect later production.
Mumps after puberty. Mumps before puberty is generally not an issue. After puberty it can cause inflammation in the testicles that occasionally affects sperm production afterwards. Many men had this and have no idea it is connected.
A twisted testicle that needed emergency surgery. Testicular torsion cuts off blood supply, and depending on how long it went untreated, it can affect that testicle’s function permanently.
Any surgery in the groin or scrotum. Including hernia repair, which is extremely common. Occasionally the tubes carrying sperm are affected during these operations.
Chemotherapy or radiation. Both can affect sperm production, sometimes temporarily and sometimes not. If this applies to you, it is essential information for whoever you see.
Serious infections, including some sexually transmitted ones. Certain infections can cause scarring that partially or fully blocks the route sperm travel.
Taking testosterone, or anabolic steroids. This one deserves its own paragraph.
The testosterone problem
If you take testosterone from an outside source, whether as prescribed treatment or otherwise, your body reads the high level in your blood and concludes it does not need to make its own. And because the signal that drives your own testosterone production is the same signal that drives sperm production, both switch off together.
Men are routinely surprised by this. It is genuinely counterintuitive: you are taking the male hormone, you feel strong, your sex drive may be excellent, and your sperm production has quietly stopped.
The good news is that it is usually reversible once you stop, though it can take months rather than weeks. The important part is not to stop any prescribed medication on your own. This is a conversation with a doctor, who will often have alternatives that protect fertility.
None of the items on this list mean something is wrong with you. They mean these are things to bring up in the first ten minutes of an appointment rather than three appointments in.
What tells you nothing at all
Here is the other side of being honest with you. Several things men worry about, sometimes for years, carry no useful information whatsoever. You can genuinely put these down.
Thick, white semen does not mean a high sperm count. Sperm are microscopic. A sample with almost no sperm and a sample packed with them look identical. What you are seeing is the fluid they travel in, which is produced by entirely different glands and has nothing to do with how many sperm are suspended in it.
A larger amount of semen does not mean more sperm. These are two separate measurements, and they are not related in the way people assume. A larger volume with a low concentration can contain fewer sperm than a small volume with a high one.
A strong sex drive does not mean healthy sperm. This goes back to the two jobs. Sex drive is hormones. Sperm is production. Different systems.
Normal erections do not mean normal fertility. Men with no sperm at all usually have completely normal erections, because erectile function has nothing to do with sperm production.
Having fathered a child before does not guarantee anything now. This one catches a lot of men off guard. Fertility is not a fixed setting. Things change: weight, health conditions, medications, a varicocele that developed since, simply getting older. A previous pregnancy is genuinely reassuring history. It is not a current guarantee, and doctors see men with a healthy child at home and a very low count today.
You would not feel it if something were wrong. By this point in the article this should be clear, but it bears repeating, because the instinct is powerful and it keeps men from getting tested.
Your partner’s normal results say nothing about yours. If you have a partner who has been tested and everything came back fine, that tells you precisely nothing about your own fertility. The two are entirely independent. This matters because it is a common reason men delay testing.
Can you check any of this at home?
Two very different things get grouped together under this question, so let’s separate them.
Looking at a sample yourself
No. Not by any method, including the ones you may have come across online.
The most common is the idea of pouring a sample into a glass of water and judging your sperm count by whether it sinks, floats or disperses. There is no science behind this. It does not measure anything at all.
The reason is straightforward. A sperm cell is far too small to see without a microscope. What you can see is the fluid, and that fluid looks essentially the same whether it contains hundreds of millions of sperm or none. Colour, thickness, smell, and how forcefully you ejaculate are all products of the fluid and the muscles involved, not of the sperm.
We can say this plainly because we have nothing to sell you. Almost every page promoting a home check of this kind is selling a supplement or a test kit, and it is worth knowing that before you read one.
Home sperm test kits
These are a genuinely different matter. They are real devices, and the better ones have been properly tested against laboratory analysis.
What they are good at is answering one narrow question: whether your sperm count looks low. For that specific purpose, the reputable ones perform reasonably well. If a clinic feels like too big a step right now, this is a legitimate first move, and for some men it is what finally gets things started.
But you should know what they do not do.
They measure less than you expect. Most look at how many sperm there are, and sometimes whether they are moving. Most do not assess the shape of the sperm, whether they are alive, or the amount of semen, all of which a clinic would look at.
They cannot tell you why. This is the more important limitation. A home kit might tell you your count is low. It cannot tell you whether that is because of a varicocele, a hormone problem, a blockage, a medication you are taking, or something temporary that will have resolved by next month. That “why” is the entire question, because it determines what can be done about it.
One result is not enough. Because production runs on a roughly three-month cycle and is affected by illness, medication and other temporary factors, sperm counts vary considerably between samples from the same man. A single low result is genuinely common and often does not repeat. This is exactly why doctors routinely test twice.
So: a reasonable first step, and better than not testing at all. Not a substitute for a proper evaluation, and definitely not something to make decisions on.
What a semen test actually looks at
If you are heading towards a test, or holding a result you do not understand, this section is for you.
A standard semen analysis looks at several separate things.
Volume is simply how much semen there is. Low volume can point towards a blockage or towards semen going the wrong way, which is why it is measured even though it says nothing directly about sperm quality.
Concentration is how many sperm there are in each millilitre of fluid. This is the number most people mean when they say “sperm count.”
Total count is concentration multiplied by volume – the number of sperm in the whole sample. This is often the more meaningful figure of the two, because it reflects total production rather than how dilute or concentrated things happened to be.
Motility is how many of the sperm are moving, and separately, how many are swimming forward in a purposeful way rather than just twitching in place. Forward movement matters, because sperm have a considerable distance to travel.
Morphology is the proportion of sperm that are normally shaped. This one causes more unnecessary alarm than any other measurement, because the proportion considered normal is much lower than people expect. Most sperm in most healthy men are imperfectly formed. That is simply how human sperm production works.
Vitality is how many are alive. This is usually only checked when motility comes back very low, to distinguish between sperm that are dead and sperm that are alive but not moving well, which are different problems with different implications.
The part almost nobody explains
Your report will have reference values printed next to each number, and this is where a great deal of unnecessary distress comes from.
Those reference values are not a pass mark.
They come from a large study of men who had no trouble conceiving, men whose partners became pregnant within a year. The figures describe what is typical among that group. Specifically, they mark the point below which the lowest few percent of fertile men fell.
Read that again, because it is the important part. Even in a group of men who all successfully conceived, some sat below those lines. The values describe a population. They do not draw a border between fertile and infertile, and the organisation that publishes them says so directly.
In practice there is enormous overlap. Men whose numbers sit below those values conceive naturally all the time. Men whose numbers sit comfortably above them sometimes struggle for years. Studies comparing pregnancy rates between men with “normal” and “abnormal” results have found the difference to be far smaller than anyone would guess from how the report looks.
This does not mean the numbers are meaningless. They are useful. They help a doctor decide what to investigate and what might help. But they are one part of a picture that also includes your partner’s fertility if you have one, timing, age, how long you have been trying, and a considerable amount of luck.
If you are reading this with a result in your hand that came back lower than you hoped, hold onto that. A number below a line is information. It is not a verdict, and it is not a conclusion about whether you will become a father.
When to get tested, and why not to be last in the queue
The general guidance is to see a doctor after twelve months of trying, or after six months if your partner is 35 or older.
Go sooner than that if anything from the history section above applies to you. There is no sense in waiting out the full twelve months when you already know something relevant.
There is one more thing worth saying clearly, because it affects a lot of couples.
The main US guidelines on male infertility recommend that both partners are assessed at the same time, not one and then the other.
In practice, that is frequently not what happens. Testing often begins with the female partner and works through a long sequence of investigations, some of them invasive, before anyone asks the man for a sample. Months disappear this way.
There is no medical reason for that order. A semen test is quick, straightforward, inexpensive compared to most fertility investigations, and involves nothing invasive at all. Given that male factors are involved in roughly half of all cases where couples struggle, it makes very little sense for it to happen last.
If you are being told to wait, or if nobody has raised it, it is entirely reasonable to ask for it yourself.
And if you are approaching this without a partner, as a single man planning ahead, or as part of a couple where nobody else needs testing, everything above applies just the same. Ask for the semen test early.
What actually happens when you go
For most men, the anticipation is considerably worse than the appointment.
The conversation. A doctor will ask about your medical history: the childhood things, surgeries, infections, medications and supplements you take, how long you have been trying, and lifestyle factors. Everything from the history section above is fair game, so it is worth thinking it through beforehand. This part matters more than people expect, and a great deal is often solved here.
The physical examination. Brief and straightforward. A doctor checks the size and consistency of the testicles and feels for a varicocele. It takes a couple of minutes.
The semen test. Usually done at the clinic, and usually repeated after a few weeks. If your doctor asks for a second one, that is not a bad sign – it is standard practice, because of the variation we described earlier.
Anything further, if needed. Depending on what turns up, this might include a blood test to check hormone levels, an ultrasound scan of the scrotum, or genetic testing. These are not routine for everyone. They get added when the first round raises a specific question.
It is worth walking in with your own questions ready rather than only answering theirs. Our guide on questions to ask your fertility doctor was written around IVF, but most of it applies equally to a first fertility appointment.
If the results are not what you hoped
A few things are worth knowing in advance, because they are rarely said early enough.
Many causes are treatable or reversible. A varicocele can often be repaired. A hormone imbalance can often be corrected. A medication can often be changed. Weight, heat exposure, smoking and several other factors can shift things meaningfully, and because production runs on that roughly three-month cycle, changes made now show up in a test around three months later. Our 90-day guide to improving male fertility covers what genuinely helps and what does not.
A very low count is not the same as no options. Modern treatment can work with remarkably small numbers of sperm. ICSI, where a single sperm is placed directly into an egg, was developed for exactly this situation.
Even a result showing no sperm is not automatically the end. This is worth stating plainly, because it is the result men fear most. The Urology Care Foundation is clear on this: depending on the cause, sperm can sometimes be found and retrieved directly, even when none appear in a sample. Whether that is possible depends on why the sperm are absent, which is precisely why the “why” matters so much.
And where that is not possible, there are still routes to becoming a parent. Using donor sperm is one of them, and it is a path many families have taken. It is not a consolation prize. It is a different route to the same place.
If this is hitting you harder than you expected
That is a very normal response, and a well-documented one.
Research on how men experience fertility difficulty consistently finds anxiety, low mood and a real knock to confidence. It also consistently finds that support for men is thin. Fertility care is largely built around the female partner, so men frequently end up carrying this without anyone asking how they are.
One finding is worth passing on directly. The men who feel this most severely tend to be the ones who most strongly connect fertility with being a man. Which means a good part of what you may be feeling right now comes from a story you absorbed somewhere along the way, not from anything true about your worth, your masculinity, or what you have to offer as a father.
Men also tend to underplay this when asked. If you have been telling everyone you are fine, you would not be the first.
If this is landing heavier than you expected, you are not overreacting.
Finding out that you might be the reason conception isn’t happening is a genuinely hard moment, and most men go through it without anyone to talk to. Lesson 9 of Understanding Male Infertility is about exactly that – the identity, the silence, and how couples navigate it together. It’s there whenever you’re ready.
The bottom line
You cannot tell whether you are fertile from how you feel, how your semen looks, or how your sex life is going. That is not a failure of self-awareness. It is simply how the body is arranged.
What you can do:
- Take your history seriously. It tells you more than any symptom ever will
- Recognise that the usual “signs” lists are describing low testosterone, not low sperm counts
- Mention the few genuine physical signs to a doctor, without reading disaster into them
- Stop drawing conclusions from appearance, volume, sex drive or how you feel generally
- Get a semen test after twelve months of trying, or six months if your partner is 35 or older
- Ask to be tested alongside your partner, not after her
And if your results come back lower than you hoped, remember what those reference values actually are. They describe fertile men. They are not a judgment on you, and they are not the end of the story.
The hidden half of the story
If you came here looking for a sign and are leaving with “get tested,” that can be a lot to sit with. Our course Understanding Male Infertility: The Hidden Half of the Story was built for exactly this point in the journey.
Lesson 1 explains why male fertility has been overlooked for so long. Lesson 3 walks through a semen analysis line by line, so the numbers stop being intimidating. Lesson 6 covers what an evaluation actually involves, before you walk into one.
No jargon, no pressure, nothing being sold to you.
This article is for education only and is not medical advice. It is not a substitute for seeing a qualified healthcare professional. Please do not stop or start any prescribed medication without speaking to your doctor. If you notice pain, swelling or a lump in your testicles, please see a doctor soon, whatever your fertility plans are.
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