Male infertility is usually found through testing, not through obvious symptoms. A man may have normal erections, normal ejaculation, and no pain but still have a low sperm count, poor sperm movement, blocked sperm transport, or a hormone problem that makes pregnancy harder. Doctors usually start with simple steps: a reproductive history, physical exam, semen analysis, and selected blood tests. More advanced tests come later when the first results point toward a specific cause.
The main goal is not to place blame. Fertility depends on both partners, and male factors are common enough that the male partner should be evaluated early, not after months of testing only the female partner. Some causes are reversible, some are treatable with procedures or medication, and some require assisted reproduction. The first results help sort those paths quickly.
Table of Contents
- How Male Infertility Is Usually Found
- The Most Common Causes Doctors Look For
- Semen Analysis: The First Test That Guides the Rest
- Hormone Testing and What the Results Suggest
- Physical Exam Clues That Can Change the Plan
- When Genetic, Imaging, or Specialized Tests Are Needed
- Common Reversible Factors Men Can Address
- What Happens After the First Results
How Male Infertility Is Usually Found
A fertility evaluation usually starts after 12 months of regular unprotected sex without pregnancy. Doctors often start earlier if the female partner is 35 or older, cycles are irregular, there is a known reproductive condition, or the man has risk factors such as prior chemotherapy, undescended testicle, testicular surgery, a history of testosterone use, or very abnormal semen results.
Male infertility does not always mean “no sperm.” It can mean the sperm count is low, sperm do not move well, many sperm have abnormal shape, sperm cannot exit the reproductive tract, or sex is not happening often enough at the right time because of erectile or ejaculation problems.
A basic male fertility workup usually includes:
- A medical and reproductive history
- A review of medications, supplements, alcohol, cannabis, nicotine, and anabolic steroid or testosterone use
- A physical exam focused on the testicles, scrotum, penis, and signs of hormone imbalance
- At least one semen analysis, and often a repeat test if results are abnormal
- Hormone blood tests when sperm count is low, sex drive is low, erections have changed, or the exam suggests a hormone problem
Couples often assume the female partner should be tested first because pregnancy happens in her body. That delay can waste time. A semen analysis is usually less invasive and less expensive than many female fertility tests, and it can quickly show whether the male partner needs a urologist, reproductive endocrinologist, or male fertility specialist.
Men with abnormal semen results may also need evaluation for general health issues. Low sperm production can sometimes overlap with hormone disorders, genetic conditions, testicular cancer risk, metabolic disease, or past injury. Fertility testing is not only about pregnancy; it can uncover health problems that deserve attention.
The Most Common Causes Doctors Look For
Most male infertility causes fall into a few broad groups: problems making sperm, problems moving sperm out, hormone signals that are too weak or disrupted, sexual function problems, and exposures that damage sperm production.
Low sperm production
Low sperm production is one of the most common findings. The semen analysis may show low sperm concentration, low total sperm count, poor motility, abnormal morphology, or no sperm at all. The cause may be obvious, such as chemotherapy, testosterone use, undescended testicle, or a genetic condition. In other cases, no single cause is found.
Common contributors include:
- Varicocele
- Prior testicular injury, torsion, infection, or surgery
- Undescended testicle, even if corrected in childhood
- Heat exposure around the testicles
- Obesity and metabolic syndrome
- Certain medications
- Anabolic steroids or testosterone therapy
- Genetic conditions affecting sperm production
A low count does not automatically mean pregnancy is impossible. It changes the odds and guides next steps. Mild abnormalities may improve with treatment or lifestyle changes. Severe abnormalities may require advanced fertility care.
Varicocele
A varicocele is an enlarged group of veins in the scrotum, often described as feeling like a “bag of worms.” It can raise testicular temperature and may affect sperm production, motility, and sometimes testosterone. Varicoceles are common, but not every varicocele causes infertility.
Doctors pay more attention when the varicocele is felt on exam, semen results are abnormal, and the couple is having trouble conceiving. A small varicocele seen only on ultrasound may not be the main problem. For a fuller explanation of symptoms and treatment choices, see varicocele and fertility impact.
Blocked sperm transport
Sperm may be produced but unable to reach the semen. This can happen after vasectomy, hernia surgery, pelvic surgery, infections, or congenital absence of the vas deferens. Blockage is especially suspected when semen volume is low, sperm are absent, testicle size is normal, and hormone levels suggest sperm production may still be active.
A man with a blockage may have normal testosterone, normal erections, and normal orgasm. The semen analysis may be the first clue.
Hormone problems
The brain and testicles work together through hormones. The pituitary gland sends follicle-stimulating hormone, or FSH, and luteinizing hormone, or LH, to the testicles. FSH supports sperm production. LH supports testosterone production.
Hormone problems may happen because the brain is not sending enough signal, the testicles are not responding well, or outside hormones are suppressing the system. Testosterone therapy and anabolic steroids are major examples because they can shut down sperm production even when blood testosterone looks high.
Sexual or ejaculation problems
Some men make sperm normally but have trouble delivering sperm into the vagina. Erectile dysfunction, delayed ejaculation, anejaculation, premature ejaculation severe enough to prevent intercourse, and retrograde ejaculation can all affect fertility.
Retrograde ejaculation means semen goes backward into the bladder instead of out through the penis. It can happen with diabetes-related nerve damage, certain medications, spinal cord issues, or prostate/bladder neck surgery. Men may notice “dry orgasm” or very low semen volume.
Infections and inflammation
Past or current infections can affect sperm production or block sperm transport. Epididymitis, prostatitis, sexually transmitted infections, and mumps orchitis are examples. Some infections cause pain, swelling, discharge, burning with urination, or fever. Others are quiet and found only during testing.
Testing depends on symptoms and risk. A semen analysis alone does not diagnose every infection. Doctors may use urine tests, STI tests, semen culture in selected cases, or exam findings.
Semen Analysis: The First Test That Guides the Rest
Semen analysis is the central first test because it shows whether sperm are present and gives a rough picture of sperm number, movement, shape, semen volume, and other features. It does not prove whether a man is fertile or infertile by itself, but it tells doctors what to check next.
A standard semen analysis usually reports:
| Result area | What it can suggest |
|---|---|
| Semen volume | Low volume may suggest collection problems, retrograde ejaculation, ejaculatory duct obstruction, low androgen effect, or missing/blocked reproductive ducts. |
| Sperm concentration | Low concentration can point toward impaired sperm production, hormone issues, varicocele, heat, toxins, medications, or genetic causes. |
| Total sperm count | This combines volume and concentration, giving a better sense of how many sperm are in the full sample. |
| Motility | Poor movement may reduce the chance of sperm reaching the egg and may be affected by varicocele, infection, oxidative stress, heat, or lab timing. |
| Morphology | Shape results can be hard to interpret alone; abnormal morphology matters more when paired with low count or poor motility. |
| pH and round cells | These may raise suspicion for inflammation, infection, or blockage, but they usually need follow-up rather than a quick conclusion. |
Collection details matter. The usual instruction is to avoid ejaculation for 2 to 7 days before the sample, collect the entire sample, and deliver it promptly if collected outside the lab. Missing the first part of the ejaculate can falsely lower the sperm count because that portion often contains many sperm.
One abnormal result is not always enough to diagnose a stable problem. Sperm production takes about three months, and semen results vary from sample to sample. Fever, hot tubs, illness, new medications, heavy alcohol use, poor sleep, and collection errors can temporarily affect results. Many doctors repeat an abnormal semen analysis before making big decisions.
Some men start with home testing. That can be useful as a first screen, but home kits vary in what they measure. Some check only sperm concentration or total count and do not fully assess motility, morphology, volume, pH, or signs of inflammation. For a deeper comparison, see what at-home sperm tests measure.
A lab-based semen analysis is still the usual test when a couple has been trying without success. A clear breakdown of result terms can help men understand why one number rarely tells the whole story; see semen analysis results and next steps for more detail.
Hormone Testing and What the Results Suggest
Hormone testing is not needed for every man with normal semen results and no symptoms, but it becomes important when sperm count is low, sperm are absent, testicles are small, libido is low, erections have changed, breast tenderness is present, or there are signs of low testosterone.
The first hormone tests often include:
- Total testosterone, usually checked in the morning
- FSH
- LH
- Sometimes prolactin, estradiol, sex hormone-binding globulin, thyroid tests, or repeat testosterone testing
FSH is especially useful when sperm count is very low or absent. High FSH can mean the pituitary is trying hard to stimulate the testicles, but the testicles are not producing sperm well. Low or normal FSH with very low sperm may point toward blockage, recent hormone suppression, or a brain/pituitary signaling problem, depending on the exam and other labs.
Testosterone results need context. A borderline low result should usually be repeated in the morning under consistent conditions. Low testosterone can affect libido and erections, but sperm production depends heavily on high testosterone levels inside the testicles, not just testosterone in the bloodstream.
A common mistake is starting testosterone therapy while trying to conceive. Outside testosterone can reduce LH and FSH signals from the brain, which can sharply lower sperm production. Some men become severely oligospermic or azoospermic while using injections, gels, pellets, or anabolic steroids. Men who want future fertility should discuss alternatives before starting treatment. More detail is available in TRT and fertility risks.
Hormone patterns can point doctors in different directions:
- Low testosterone with high LH and high FSH may suggest primary testicular failure.
- Low testosterone with low or normal LH and FSH may suggest secondary hypogonadism, pituitary issues, obesity-related suppression, medication effects, or anabolic steroid/testosterone suppression.
- High prolactin can lower sexual function and suppress reproductive hormones.
- High estradiol may be seen with obesity, certain medications, liver disease, or hormone manipulation.
Hormone testing should not be interpreted from one number alone. Doctors match the labs with testicle size, semen results, symptoms, medications, and timing.
Physical Exam Clues That Can Change the Plan
A focused exam can reveal causes that blood tests and semen testing may miss. Many men feel awkward about this part, but it is often quick and important. The exam usually checks testicle size and firmness, the epididymis, vas deferens, scrotal veins, penis anatomy, body hair pattern, and breast tissue.
Small, soft testicles may suggest reduced sperm production. A missing vas deferens may suggest a congenital condition linked with cystic fibrosis gene variants. A swollen or firm epididymis may suggest blockage or prior inflammation. A testicular lump needs prompt evaluation because fertility problems and testicular tumors can overlap in some men.
Doctors also look for signs of hormone imbalance, such as reduced body hair, gynecomastia, low muscle mass, or obesity centered around the abdomen. These findings do not diagnose infertility by themselves, but they help decide which labs are worth ordering.
A varicocele is usually checked while standing and sometimes while bearing down. The side matters too. Most varicoceles are on the left. A new, sudden, or isolated right-sided scrotal vein enlargement may need closer evaluation because it is less typical.
Pain changes the urgency. Infertility testing is usually not an emergency, but sudden severe testicular pain can be testicular torsion, which needs emergency care. Ongoing aching, swelling, or a lump should not be ignored. A guide to testicular pain warning signs can help separate routine evaluation from urgent symptoms.
The exam also gives a chance to discuss sexual function directly. Some men do not volunteer erection, ejaculation, or timing problems unless asked. These issues are medical, common, and often treatable. When sperm production is normal but intercourse or ejaculation is not happening reliably during the fertile window, treating sexual function may be the most direct fertility step.
When Genetic, Imaging, or Specialized Tests Are Needed
Advanced testing is usually guided by the first results. Ordering every possible test at the beginning can create confusion, cost, and false alarms. Doctors usually add tests when semen analysis, hormone results, or the exam points to a narrower question.
Genetic testing
Genetic testing is often considered when sperm concentration is extremely low or sperm are absent. Common tests include a karyotype, Y-chromosome microdeletion testing, and CFTR gene testing in men with missing vas deferens or suspected obstructive azoospermia.
A karyotype looks at chromosomes. It can identify conditions such as Klinefelter syndrome, where a man usually has an extra X chromosome. Y-chromosome microdeletion testing looks for missing genetic regions needed for sperm production. CFTR testing is important when the vas deferens is absent because that finding can be linked with cystic fibrosis carrier status.
These results can affect treatment and family planning. Some genetic findings may affect sperm retrieval chances. Others may be passed to children, so genetic counseling may be recommended.
Imaging
Scrotal ultrasound may be used when the exam is unclear, testicle size needs confirmation, a lump is suspected, or varicocele details need clarification. It is not always needed for every man with infertility.
Transrectal ultrasound may be used when doctors suspect ejaculatory duct obstruction, especially with low semen volume, acidic semen, absent or very low sperm, and normal-sized testicles. Kidney imaging may be considered when the vas deferens is absent because reproductive duct development and urinary tract development can overlap.
Sperm DNA fragmentation testing
Sperm DNA fragmentation testing looks at damage to sperm genetic material. It is not part of every first evaluation. It may be considered in certain situations, such as unexplained infertility, repeated pregnancy loss, failed assisted reproduction, varicocele with unclear significance, or major exposure risks.
A high result does not always identify one simple fix. Doctors may look for varicocele, smoking, heat exposure, infection, obesity, oxidative stress, or long abstinence intervals. Sometimes treatment focuses on correcting a cause; sometimes it changes the assisted reproduction plan.
Azoospermia workup
Azoospermia means no sperm are seen in the ejaculate. It should usually be confirmed with repeat testing and careful lab processing. The main question is whether sperm production is severely impaired or sperm are being produced but blocked.
Clues favoring obstruction include normal testicle size, normal FSH, low semen volume in some cases, and physical findings such as absent vas deferens or full epididymis. Clues favoring impaired production include small testicles and high FSH. The distinction matters because obstructive azoospermia may be treated with reconstruction or sperm retrieval, while nonobstructive azoospermia often requires a different plan. For more detail, see azoospermia causes and treatment options.
Common Reversible Factors Men Can Address
Sperm production changes slowly. When a cause is reversible, improvement often takes about three months or longer because new sperm need time to develop. That timeline can be frustrating, but it also means recent habits, illness, or exposures may explain a temporary drop.
Heat is a common factor. Testicles sit outside the body because sperm production works best at a slightly cooler temperature. Frequent hot tubs, saunas, heated seats, tight heat-trapping clothing, laptops on the lap, and fever can affect semen results in some men. Avoiding heat is not a cure-all, but it is a low-risk step when results are abnormal. More detail is available in how hot tubs and sauna heat affect sperm.
Nicotine, heavy alcohol use, cannabis, and recreational drugs can also affect sperm quality. The degree varies by person and exposure. Men do not need to be perfect to improve fertility odds, but cutting back or stopping harmful exposures is one of the few changes that can improve both fertility and general health.
Body weight matters too. Obesity can affect testosterone, estradiol, inflammation, sleep apnea risk, and scrotal heat. Weight loss may improve hormone patterns and sometimes semen parameters, especially when paired with better sleep, resistance training, and treatment of diabetes or metabolic syndrome.
Medication review is important. Some drugs can affect ejaculation, libido, erections, or sperm production. Examples include testosterone, anabolic steroids, some opioids, some antidepressants, some hair-loss or prostate medications, chemotherapy, and certain anti-androgen drugs. Men should not stop prescribed medication abruptly, but they should tell the fertility specialist everything they take, including supplements and injections.
Supplements are a mixed area. Antioxidants, zinc, folate, CoQ10, carnitine, and other products are often marketed for sperm health. Some may help selected men, but supplements do not fix a blocked duct, genetic cause, untreated varicocele, or testosterone-induced sperm suppression. They can also be contaminated or overdosed. A cautious overview of male fertility supplements can help separate reasonable options from exaggerated claims.
Timing of sex is another fixable issue. Intercourse every 1 to 2 days during the fertile window is often enough. Long abstinence may increase semen volume but can worsen motility or DNA fragmentation in some situations. Very frequent ejaculation can lower the count per sample but may still work for natural conception if timing is right. Couples should avoid turning sex into a rigid performance schedule, but they should understand the fertile window.
What Happens After the First Results
The next step depends on the pattern. Doctors do not treat “male infertility” as one condition; they treat the cause when one can be found and choose a fertility path when it cannot.
If the semen analysis is mildly abnormal, the doctor may repeat it, review collection conditions, check for recent fever or heat exposure, and address lifestyle or medication factors. If results improve, the couple may continue trying naturally or consider simpler fertility treatments depending on age and time trying.
If the sperm count is very low, doctors usually move faster. Hormone testing, genetic testing, and referral to a reproductive urologist may be appropriate. The female partner’s age and ovarian reserve also matter because waiting several months for possible improvement may not be wise in every couple.
If a varicocele is likely contributing, options may include repair, observation, or assisted reproduction. Repair is more often considered when the varicocele is palpable, semen results are abnormal, and the couple has infertility. Improvement, when it happens, usually takes months.
If testosterone or anabolic steroid use is suppressing sperm, the plan may involve stopping the suppressing hormone under medical supervision and using fertility-preserving medications in selected cases. Recovery can take months and is not guaranteed, especially after long-term or high-dose use.
If there is no sperm in the semen, doctors first confirm the result and then sort obstructive from nonobstructive azoospermia. Some men can have sperm retrieved from the testicle or epididymis for IVF with ICSI. Some may be candidates for surgical reconstruction. Others may need donor sperm, adoption, or other family-building options after counseling.
If sexual function is the main barrier, treatment may involve erectile dysfunction medication, counseling, timing changes, medication adjustments, or treatment for diabetes, low testosterone signaling, anxiety, pelvic pain, or ejaculation disorders.
A fertility specialist is especially useful when:
- The semen analysis shows no sperm or very low sperm count
- Results are abnormal on repeat testing
- The man has a history of chemotherapy, testicular surgery, undescended testicle, or anabolic steroid/testosterone use
- There is a palpable varicocele with abnormal semen results
- The couple has recurrent pregnancy loss
- The female partner is 35 or older
- The couple has been trying for a year, or for six months when age or known risk factors make earlier care sensible
A clear plan reduces wasted time. For many couples, the answer is not one dramatic diagnosis but a combination of small factors: borderline sperm count, irregular timing, older reproductive age, heat exposure, weight gain, or a medication that affects ejaculation. For others, the first semen analysis points quickly to a specialist-level issue. Knowing when to escalate can prevent months of guessing; see when to see a fertility specialist for timing and expectations.
References
- Updates to Male Infertility: AUA/ASRM Guideline (2024) 2024 (Guideline)
- WHO laboratory manual for the examination and processing of human semen, 6th ed 2021 (Manual)
- European Association of Urology Guidelines on Male Sexual and Reproductive Health: 2025 Update on Male Infertility 2025 (Guideline)
- 2023 Canadian Urological Association guideline: Evaluation and management of azoospermia 2023 (Guideline)
- A Review of Semen Analysis: Updates From the WHO Sixth Edition Manual and Advances in Male Fertility Assessment 2024 (Review)
- Recent Trends in the Management of Varicocele 2025 (Review)
Disclaimer
This article is for educational purposes and does not replace care from a qualified clinician. Male infertility testing and treatment should be guided by a healthcare professional, especially when semen results are severely abnormal, hormones are low, pain or swelling is present, or medications such as testosterone or anabolic steroids are involved. Couples should be evaluated together because timing, age, and both partners’ health affect the best next step.
