Male Infertility Overview: Causes, Diagnosis, and Treatment Options for Men

Infertility affects millions of couples worldwide, and in nearly half of all cases, the male partner plays a contributing role. Male infertility refers to a man’s inability to impregnate a woman after one year of regular, unprotected sexual intercourse. This can be due to issues with sperm production, sperm function, ejaculation, or hormonal imbalances.

This comprehensive guide will walk you through the key causes of male infertility, how it’s diagnosed, and the most effective treatments available today—including lifestyle changes, medical therapies, and assisted reproductive techniques.

What Is Male Infertility?

Male infertility refers to a man’s inability to cause pregnancy in a fertile female partner after 12 months of regular, unprotected sexual intercourse. It is a complex condition that can result from problems with sperm production, sperm quality, hormonal imbalances, ejaculation disorders, or anatomical blockages.

While infertility is often perceived as a female issue, male factors contribute to approximately 40–50% of all infertility cases—and in about 20–30% of cases, the problem lies solely with the male partner.

When Should a Man Be Evaluated?

You should consider a fertility evaluation if:

• You and your partner have tried to conceive for 12 months or more without success
• You have a history of testicular, prostate, or sexual health issues
• You’ve undergone cancer treatment (chemotherapy or radiation)
• You have erectile or ejaculatory dysfunction
• You have a known low sperm count or hormonal imbalance
• You are over age 40 and trying to conceive for the first time

📌 Tip: If your partner is over 35, both partners should begin evaluation after just 6 months of trying.

How Is Male Fertility Measured?

Male fertility is primarily assessed by evaluating sperm health, including:

• Sperm count: Number of sperm per milliliter of semen
• Motility: How well the sperm move
• Morphology: The shape and structure of the sperm
• Volume: The total amount of semen in each ejaculation
• Viability: The percentage of live sperm

✅ Semen analysis is the cornerstone of male infertility testing, typically performed after 2–7 days of sexual abstinence.

Male infertility can be a temporary condition, a reversible problem, or in some cases, a more permanent challenge—but it is always worth investigating early. Timely diagnosis improves the chances of successful treatment and, in many cases, natural conception.

Common Causes of Male Infertility

Male infertility can result from a wide range of issues, including problems with sperm production, hormonal imbalances, blockages in the reproductive tract, or lifestyle and environmental exposures. Often, more than one factor may be involved.

Let’s explore the most common causes in more detail:

1. Sperm Production Problems

This is the most frequent cause of male infertility and includes:

• Oligospermia – low sperm count
• Azoospermia – complete absence of sperm in the semen
• Teratozoospermia – abnormally shaped sperm
• Asthenozoospermia – poor sperm motility

Common causes include:

• Genetic conditions (e.g., Klinefelter syndrome)
• Testicular injury or trauma
• Undescended testicles (cryptorchidism)
• Hormonal imbalances affecting sperm development
• Exposure to heat, toxins, or radiation

📌 Note: Some men produce sperm in the testicles but cannot release it due to an obstruction or ejaculatory problem.

2. Hormonal Imbalances

Male fertility depends on a delicate balance of hormones, particularly testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH).

Disruptions in hormone production can reduce sperm production or quality. Causes include:

• Hypogonadism (low testosterone)
• Pituitary gland disorders
• Thyroid dysfunction
• Elevated prolactin levels
• Use of anabolic steroids

3. Ejaculation Disorders

Ejaculatory dysfunction can prevent sperm from reaching the female reproductive tract.

Examples include:

• Retrograde ejaculation – semen flows backward into the bladder
• Anejaculation – complete absence of ejaculation
• Premature ejaculation (in some fertility cases, sperm fails to reach cervix)
• Ejaculatory duct obstruction – mechanical blockage in the ducts that transport sperm

These conditions may result from diabetes, nerve damage, surgery, medications, or psychological factors.

4. Varicocele

A varicocele is an enlargement of the veins within the scrotum, similar to varicose veins in the legs. It’s one of the most common reversible causes of male infertility.

Varicoceles can:

• Increase scrotal temperature
• Impair sperm production and function
• Lead to oxidative stress on sperm cells

✅ Tip: Varicoceles are often diagnosed via physical exam or scrotal ultrasound and can be treated surgically.

5. Genetic or Congenital Abnormalities

Some men are born with abnormalities that affect fertility:

• Congenital absence of the vas deferens (CBAVD) – often linked to cystic fibrosis
• Klinefelter syndrome – extra X chromosome (XXY)
• Y chromosome microdeletions – impact sperm production

Genetic testing is often recommended in cases of azoospermia or very low sperm counts.

6. Lifestyle and Environmental Factors

Certain habits and exposures can reduce sperm quality and count:

• Smoking
• Heavy alcohol consumption
• Illicit drug use (especially marijuana and steroids)
• Obesity
• Chronic stress
• Sleep deprivation
• Exposure to environmental toxins (e.g., pesticides, heavy metals, plastic chemicals)

📌 Note: Lifestyle changes are often the first step in improving male fertility—especially when no structural abnormality is found.

7. Infections and Inflammation

Certain infections can affect sperm production or block sperm delivery:

• Sexually transmitted infections (e.g., chlamydia, gonorrhea)
• Prostatitis or epididymitis
• Mumps orchitis (especially after puberty)

⚠️ Untreated infections can cause scarring or permanent damage to the reproductive tract.

8. Structural Blockages and Physical Trauma

Blockages in the reproductive tract can prevent sperm from being ejaculated, even if sperm production is normal.

Causes include:

• Vasectomy (intentional)
• Scar tissue from surgery or infections
• Trauma to the testicles, groin, or lower back
• Tumors (benign or cancerous)

Male infertility can stem from a single issue or a combination of factors. That’s why a full diagnostic workup is essential to pinpoint the exact cause and guide treatment effectively.

Symptoms and Signs of Male Infertility

Unlike many health conditions, male infertility often presents with few or no obvious symptoms. Most men only discover there may be an issue after months or years of trying to conceive without success. However, in some cases, infertility may be accompanied by specific signs or related health problems.

Here’s what to watch for:

1. Inability to Conceive

This is the primary sign of male infertility—failure to achieve pregnancy with a female partner after 12 months of regular, unprotected sex (or 6 months if the female partner is over 35).

It’s important to remember that male fertility issues are not always linked to sexual performance. A man can have normal libido and erections, yet still have poor sperm quality or low sperm count.

2. Sexual Dysfunction

In some cases, infertility may be accompanied by sexual issues, such as:

• Erectile dysfunction (ED)
• Reduced libido or sexual desire
• Difficulty with ejaculation or anorgasmia
• Low semen volume

These symptoms may signal hormonal imbalances, nerve dysfunction, or other reproductive issues.

3. Pain, Swelling, or Discomfort

Certain physical signs may suggest underlying structural or medical problems:

• Pain or swelling in the testicles (e.g., from varicocele, infection, or trauma)
• Lump or mass in the scrotum
• Discomfort during or after ejaculation
• Persistent pelvic or groin pain

📌 Tip: Any pain or noticeable change in the scrotal area should be evaluated by a healthcare provider.

4. Signs of Hormonal Imbalance

Fertility problems may also result from disrupted testosterone production, often with additional signs like:

• Decreased facial or body hair
• Loss of muscle mass
• Gynecomastia (breast tissue development)
• Mood changes or fatigue

These symptoms may point to hypogonadism or pituitary disorders.

5. History of Related Conditions

If any of the following apply, fertility may be at risk—even if symptoms are mild:

• Undescended testicles (in childhood or not corrected)
• Previous testicular trauma or surgery
• Infections like mumps orchitis or STIs
• Cancer treatments (radiation, chemotherapy)
• Use of anabolic steroids or testosterone therapy

⚠️ Some causes of infertility don’t produce symptoms at all, which is why testing is crucial.

In many cases, male infertility is a silent condition—without obvious warning signs. That’s why couples who struggle to conceive should not delay evaluation, even if the man feels healthy or has no noticeable symptoms.

How Male Infertility Is Diagnosed

Diagnosing male infertility involves a combination of medical history review, physical examination, and specialized lab tests to evaluate sperm health, hormone levels, and possible anatomical or genetic issues. It’s a structured but non-invasive process in most cases.

Here’s what you can expect during an infertility workup:

1. Medical and Sexual History

The evaluation typically begins with a comprehensive history that covers:

• Duration of attempts to conceive
• Frequency of intercourse and any sexual difficulties
• Past medical conditions or surgeries (especially testicular, prostate, or pelvic)
• History of STIs or infections
• Exposure to toxins, heat, radiation, or chemicals
• Lifestyle habits (smoking, alcohol, drug use)
• Use of medications, supplements, or anabolic steroids
• Family history of infertility or genetic disorders

📌 Tip: Be honest and detailed. A full history helps your doctor target the most likely causes.

2. Physical Examination

A focused physical exam may include:

• Testicular size and consistency
• Presence of varicocele (enlarged veins in the scrotum)
• Signs of hormonal imbalance (e.g., breast tissue, low muscle mass)
• Evaluation of penis, epididymis, and vas deferens for blockages or congenital absence
• Digital rectal exam (if prostate issues are suspected)

3. Semen Analysis

This is the cornerstone test in diagnosing male infertility.

You’ll be asked to provide a semen sample, usually after 2–7 days of abstinence, which will be analyzed for:

• Volume (normal: ≥1.5 mL)
• Sperm concentration (normal: ≥15 million/mL)
• Motility (progressive movement: ≥32%)
• Morphology (normal shape: ≥4% normal forms by strict criteria)
• Vitality (percentage of live sperm)
• White blood cells (may indicate infection)

✅ Sometimes, multiple semen analyses are needed to confirm results due to natural variability.

4. Hormonal Testing

If sperm count is low or absent, blood tests are ordered to check reproductive hormone levels:

• Total and free testosterone
• LH (Luteinizing Hormone)
• FSH (Follicle-Stimulating Hormone)
• Prolactin
• Estradiol (if gynecomastia or obesity present)
• Thyroid function (TSH)

📌 Low testosterone with high FSH and LH may indicate primary testicular failure. Low FSH/LH suggests secondary (pituitary) dysfunction.

5. Genetic Testing (If Indicated)

Genetic evaluation may be recommended in cases of:

• Non-obstructive azoospermia (no sperm in semen)
• Very low sperm counts
• Suspected congenital abnormalities (e.g., absence of vas deferens)

Common tests include:

• Karyotyping (to detect chromosomal abnormalities like Klinefelter syndrome)
• Y-chromosome microdeletion testing
• CFTR gene testing (if vas deferens is absent)

6. Imaging and Specialized Tests

If a structural issue is suspected, imaging may help:

• Scrotal ultrasound – to check for varicocele, masses, or blockages
• Transrectal ultrasound (TRUS) – evaluates the ejaculatory ducts and seminal vesicles
• Post-ejaculatory urinalysis – detects retrograde ejaculation (presence of sperm in urine)
• Testicular biopsy – in some cases of azoospermia to distinguish between production and obstruction

Summary of Diagnostic Steps: