Male infertility under the microscope: Sperm are disappearing, quality has dropped by 50% in 40 years 

Male fertility is collapsing. And hardly anyone talks about it. Every second case of infertility originates in the male body. Yet, it remains a topic that is overlooked, downplayed, and wrapped in silence. In 2025, male fertility is dramatically declining — according to WHO data, the average quality of sperm has dropped by 50% over the last 40 years. In Europe, every third couple struggles to conceive. Meanwhile, a semen analysis takes just a few minutes.

What can cause male infertility?

You may feel healthy, exercise regularly, and live a normal life — yet you hold a semen analysis result showing something is wrong. Male infertility often comes without warning. On the contrary, many men only learn about the problem when they and their partner fail to conceive.

Genetics and hormones: Often hidden causes

Although it may seem surprising, there are many causes — from genetic disorders through hormonal imbalances to lifestyle factors. Let’s go through them step by step and see how they manifest in practice.

Interesting fact: According to a recent study, up to 15% of men treated for infertility suffer from genetically caused spermatogenesis disorders. One of the most common diagnoses is Klinefelter syndrome. This genetic disorder means a man has an extra sex chromosome (XXY) instead of the usual two (XY). This condition can lead to reduced testosterone production, fertility problems, and other physical or developmental differences.

Genes, hormones, or silent infection? These can also be the cause

V některých případech za neplodností stojí genetická mutace, o které jste doteď neměli ani tušení. V jiných hraje roli hormonální nerovnováha, třeba snížená hladina testosteronu, která se dá řešit pomocí léčby. A někdy problém způsobí infekce, která dávno proběhla bez příznaků, ale zanechala po sobě stopy. Nejčastěji se jedná o pohlavně přenosné infekce, jako jsou chlamydie, kapavka nebo mykoplazmata. Ty mohou poškodit chámovody nebo varlata, a tím snížit plodnost. Vzácněji však mohou mít vliv i jiné infekce, například příušnice v dospělosti, tuberkulóza nebo silné horečnaté onemocnění, které naruší tvorbu spermií.

In some cases, infertility is caused by a genetic mutation you never knew about. In others, hormonal imbalance plays a role — for example, low testosterone levels that can be treated. Sometimes, an infection causes the problem, often one that passed without symptoms but left lasting damage. The most common are sexually transmitted infections such as chlamydia, gonorrhea, or mycoplasma. These can damage the vas deferens or testes, reducing fertility. Less commonly, other infections like adult mumps, tuberculosis, or severe febrile illnesses can disrupt sperm production.

Interesting fact: Sources report that up to 50% of men with untreated chlamydia infections are unaware they have it — because there are no symptoms. That’s why chlamydia can quietly damage fertility.

Lifestyle: What do extra kilos and stress have to do with it?

Důležité je vědět, že i životní styl má velký vliv. Pokud kouříte, často saháte po alkoholu, máte nadváhu nebo prožíváte chronický stres, spermie to poznají. Ne hned, ale časem rozhodně. Například v časopise Obesity Reviews se dočtete, že obézní muži mají vyšší pravděpodobnost neplodnosti ve srovnání s muži s normální hmotností. K výsledku vedla studie, která zahrnovala analýzu 30 jiných studií s více než 115 000 účastníky. Vyšlo tak najevo, nakolik je obezita spojená s horšími hodnotami spermií, a to včetně snížené koncentrace, motility a morfologie spermií.

It’s important to know that lifestyle has a major impact as well. If you smoke, frequently drink alcohol, are overweight, or experience chronic stress, your sperm will feel it. Maybe not immediately, but certainly over time. For example, the journal Obesity Reviews reported that obese men have a higher risk of infertility compared to men with normal weight. This conclusion came from an analysis of 30 other studies involving over 115,000 participants. It revealed how obesity is linked to poorer sperm parameters, including reduced concentration, motility, and morphology.

Interesting fact: According to WHO data from 2024, every third couple in Europe faces fertility problems, and in more than half of the cases, the man is responsible.

Tip: Get inspired by our article Gentlemen, train yourselves for conception.

Steroidy a léky? Můžou plodnost pěkně rozhodit

Spousta mužů do sebe sype anabolika, aniž by tušila, co to udělá s plodností. Steroidy tělu dají signál: ​„Testosteronu máme dost,“ a to pak přestane vyrábět vlastní – a s tím jdou ke dnu i spermie. Stejně tak třeba finasterid, který se bere na padání vlasů, může snížit objem ejakulátu nebo zhoršit kvalitu spermií. Než něco začnete brát dlouhodobě, radši to konzultujte s doktorem.

Práce, která vás může stát i dítě

A nakonec tu máme prostředí, kde pracujete. Dlouhodobý kontakt s chemikáliemi, těžkými kovy nebo vysokými teplotami (například v kuchyních, továrnách/​výrobních provozech nebo dílnách) může poškodit kvalitu spermií. I to je důvod, proč lékaři při diagnostice vždy chtějí znát vaši profesi.

What does a male fertility examination look like?

It might sound scary, but testing for male infertility is nothing complicated. You won’t face anything painful — just a few practical steps that together create a clear picture of your fertility status.

Tip: Read our article Male Fertility Is No Longer a Taboo.

It starts simply — with a conversation with the doctor. They will ask about your medical history, lifestyle, and work environment. Then comes a routine physical exam, which includes checking your testicles, scrotum, and groin area.

After that, specific tests follow:

• Semen analysis (spermiogram) – the most important test that reveals how many sperm you produce, how they move, and what they look like. You can provide the sample directly at the clinic or collect it at home and then deliver it to the lab according to the medical facility’s instructions.
• Hormone tests – blood samples measure key hormone levels such as FSH, LH, and testosterone. These hormones influence whether your body even receives the signal to produce sperm.
• Genetic tests – if the semen analysis results are poor, the doctor may recommend genetic testing. This can detect conditions like Klinefelter syndrome or other abnormalities.
• Testicular ultrasound – ultrasound is used to check for inflammation, cysts, or enlarged veins (called varicocele) that might interfere with fertility.

Interesting fact: According to WHO, a healthy sperm count is 15 million/​ml or at least 39 million per ejaculate.

Infertility and psyche: An area men don’t like to talk about

If you and your partner are having trouble conceiving, there’s no need to panic right away. There are many ways to address male infertility. The key is to identify the cause and choose the appropriate treatment accordingly.

According to research from 2024, up to 39% of men suffering from infertility go through a period of psychological stress and uncertainty about their male identity. Infertility is not your fault — and it’s certainly not something that should define your worth. Don’t be afraid to talk about it. With your partner, with your doctor, with a psychologist. Often that alone is enough to make you feel a little better.

Treatment and Support for Male Fertility: What Are Your Options?

Pokud se vám s partnerkou nedaří počít dítě, není třeba hned propadat panice. Existuje řada možností, jak řešit mužskou neplodnost. Důležité je zjistit příčinu a podle ní zvolit vhodnou léčbu.

1. Infection Treatment

If infertility is caused by an infection, such as chlamydia or gonorrhea, the doctor will prescribe antibiotics. It’s important that both partners undergo treatment simultaneously to prevent reinfection. Treatment usually lasts 2 – 3 weeks, but it can be longer for chronic infections.

2. Hormonal Therapy

If you have low testosterone levels or other hormonal imbalances, your doctor will likely recommend hormonal therapy. This helps regulate hormone levels and improve sperm production.

3. Surgical Procedures

In some cases, male infertility is caused by varicocele, an enlargement of veins in the scrotum. This condition can be treated with microsurgery, which improves blood flow and consequently sperm quality.

4. Assisted Reproduction

If natural conception fails and previous treatments don’t work, assisted reproduction comes into play. The most common methods include intrauterine insemination (IUI) — a simple procedure where prepared sperm (cleaned of fluid, inactive or damaged sperm and enriched with the highest quality, most motile sperm) are placed directly into the uterus at the optimal time of ovulation. For more complex situations, in vitro fertilization (IVF) is recommended — fertilization of the egg outside the woman’s body. Usually, you can choose from several approaches based on your situation:

• IVF with own eggs – the most common option if the woman produces healthy eggs.
• IVF with donor eggs – suitable if eggs are not available or are of poor quality.
• IVF with both own and donor eggs — a combined cycle to increase chances of success.
• IVF with donor embryos – an option for couples who cannot use their own reproductive cells.

5. Dietary Supplements

You can also support sperm quality by taking supplements containing vitamins C, E, B6, zinc, selenium, or herbs like Tribulus terrestris and maca (a root plant from Peru). These substances promote sperm production and overall fertility. 
Remember, every case is individual. It’s important to consult with a specialist who will help you find the best solution for your situation.

What can you do right now?

You don’t have to wait for the test results. There are a few simple things that can help your fertility today:

• Wear looser underwear – sperm don’t like the heat.
• Skip the sauna and long, hot baths.
• Don’t put your laptop on your lap – it raises the temperature in the testicular area.
• Move around, but sensibly – excessive exercise (especially with anabolics) can harm you.
• Try to limit stress – even a simple walk helps.

According to UrologyHealth (2024), following these principles can improve sperm quality in as little as 3 months — the time it takes the body to ​“replace” sperm.

You’re not alone in this — there is a solution

Disappointment, uncertainty, worry… male infertility is a difficult topic to broach. But if you let it lie under the lid, it won’t go away. Fortunately, today there are ways to find out the cause and start down the path to a solution — whether through lifestyle changes, treatment or assisted reproduction.

At the Prague Fertility Centre, you’ll meet an experienced team of doctors who will look at the situation with you in a human, open and no-nonsense way. And most importantly — they will propose a solution that will fit your needs. Whether it’s diagnostics, treatment or modern methods like IVF. If you would like more information, please contact us and we will be happy to explain everything to you.

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