Male infertility myths debunked: What a Reproductive Urologist wants every man to know

Infertility affects millions of couples worldwide, and male factors contribute to roughly 50% of all infertility cases. Despite its prevalence, male infertility remains surrounded by stigma, misconceptions, and outdated beliefs that can delay diagnosis and treatment. 

Understanding the facts about male fertility is an important step toward improving reproductive outcomes and empowering couples on their fertility journey. In this article, reproductive urologist Dr. Justin Houman addresses some of the most common myths about male infertility and shares what the latest research tells us about sperm health, fertility, and reproductive wellness.

Does tight underwear cause male infertility?

One of the most common questions men ask is whether wearing briefs instead of boxers can negatively affect fertility.

The age-old boxers versus briefs debate has led many people to believe that tight underwear harms fertility by increasing scrotal temperature. While sperm production is sensitive to heat, research suggests that underwear choice alone is unlikely to significantly impact fertility.

A study published in Human Reproduction found no meaningful difference in sperm quality between men who wore tighter underwear and those who chose looser styles. More recent research examining male heat exposure and fertility found that prolonged exposure to heat sources such as hot tubs, saunas, and hot baths may negatively affect sperm parameters, while underwear choice appears to have minimal impact.

Rather than focusing on boxers versus briefs, men trying to conceive may benefit more from limiting frequent heat exposure from hot tubs, saunas, heated seats, and prolonged laptop use directly on the lap.

Does male age affect fertility and sperm health?

Many people are aware of the impact of female age on fertility, but fewer realize that male fertility also changes over time.

While men do not experience menopause, sperm quality gradually declines with age. Research has shown that advanced paternal age is associated with reductions in sperm motility, increases in sperm DNA fragmentation, and a longer time to conception.

Recent reviews have also linked older paternal age with an increased risk of certain genetic and neurodevelopmental conditions in offspring, including autism spectrum disorders and schizophrenia. Scientists continue to investigate how age-related genetic and epigenetic changes in sperm may influence reproductive outcomes.

Although many men successfully father children later in life, understanding the role of age in male fertility can help couples make informed family-planning decisions.

Is male infertility always permanent?

A common misconception is that male infertility is a permanent condition with few treatment options.

In reality, many causes of male infertility are treatable or manageable. The appropriate treatment depends on identifying the underlying cause, which may include hormonal imbalances, anatomical conditions, lifestyle factors, genetic conditions, or environmental exposures.

Treatment options may include:

• Lifestyle modifications
• Nutritional support
• Medication
• Hormone therapy
• Surgery, including varicocele repair
• Assisted reproductive technologies such as IVF and ICSI

Emerging areas of research are also exploring regenerative therapies and novel approaches to improving testicular function, although these remain investigational.

The important takeaway is that a diagnosis of male infertility does not necessarily mean a couple cannot conceive.

Do lifestyle factors impact male fertility?

Absolutely.

Lifestyle choices play a major role in sperm health and overall reproductive function. Research consistently shows that smoking, excessive alcohol consumption, recreational drug use, obesity, poor diet, and chronic stress can negatively affect sperm quality.

A review published in Human Reproduction Update found that smoking is associated with reductions in sperm concentration, motility, and morphology. Additional research suggests that obesity can contribute to hormonal imbalances and increased inflammation, both of which may impair fertility.

Nutrition also matters. Diets rich in antioxidants, omega-3 fatty acids, vitamins, minerals, fruits, vegetables, and high-quality proteins have been associated with improved sperm parameters and reproductive outcomes.

Emerging evidence suggests that sleep quality and exposure to environmental toxins, including endocrine-disrupting chemicals such as BPA and phthalates, may also influence male fertility.

When it comes to fertility, healthy habits support both partners.

Does age affect male fertility?

Although this topic overlaps with the biological clock discussion, it deserves special attention because many men are unaware of the measurable changes that occur in sperm over time.

Research published in Fertility and Sterility has shown that men over age 40 may experience:

• Increased sperm DNA fragmentation
• Reduced sperm motility
• Lower semen volume
• Increased time to pregnancy
• Higher rates of miscarriage
• Greater risk of certain health conditions in offspring

This does not mean men cannot conceive later in life. Rather, it highlights the importance of proactive fertility planning and optimizing reproductive health well before conception.

Does male reproductive anatomy affect fertility?

Male reproductive anatomy plays a critical role in fertility.

One of the most common anatomical causes of male infertility is varicocele, an enlargement of veins within the scrotum that can impair sperm production and function. Varicoceles affect approximately 15% of men and are more common among men experiencing fertility challenges.

Research has shown that varicocele repair can improve sperm parameters and may increase the likelihood of natural conception in appropriately selected patients.

Other anatomical factors that may impact fertility include:

• Obstructions within the reproductive tract
• Undescended testicles
• Congenital absence of the vas deferens
• Prior surgeries or injuries affecting reproductive organs

A reproductive urologist can help identify these conditions and determine the most appropriate treatment plan.

Frequently asked questions about male fertility

What causes male infertility?

Male infertility can result from hormonal imbalances, varicoceles, genetic conditions, lifestyle factors, environmental exposures, certain medications, infections, or anatomical abnormalities affecting sperm production or delivery.

Can male infertility be reversed?

Many forms of male infertility can be improved or treated through lifestyle changes, medical therapies, surgical intervention, or assisted reproductive technologies.

At what age does male fertility decline?

Research suggests that sperm quality gradually declines after age 40, although fertility potential varies significantly between individuals.

How can men improve sperm health naturally?

Men can support healthy sperm production by maintaining a healthy weight, exercising regularly, prioritizing sleep, managing stress, avoiding smoking, limiting alcohol, reducing toxin exposure, and ensuring adequate intake of key fertility nutrients.

Male infertility is common, but it is also frequently misunderstood. By separating fact from fiction, couples can make more informed decisions about their reproductive health and seek appropriate support when needed. Whether fertility challenges stem from age, lifestyle factors, anatomy, or other underlying conditions, early evaluation and intervention can make a meaningful difference.

If you and your partner are struggling to conceive, consider consulting with a reproductive urologist or fertility specialist who can provide personalized recommendations based on your unique situation.

Fertility is a shared journey, and both partners deserve equal attention and support throughout the process.

A note from WeNatal on supporting optimal sperm health

When conversations about fertility begin, the focus often falls on women. Yet sperm contribute half of the genetic material that creates a future child, making male reproductive health an essential part of the preconception journey.

Research continues to show that nutrition, lifestyle habits, environmental exposures, stress, sleep quality, and age all influence sperm quality, including sperm count, motility, morphology, and DNA integrity.

At WeNatal, we believe fertility preparation should support both partners. That's why WeNatal for Him was formulated with science-backed nutrients that help support healthy sperm production, antioxidant protection, cellular energy production, and reproductive wellness.

WeNatal for Him includes:

• Methylated folate and B vitamins to support DNA synthesis and methylation
• Zinc and selenium to support normal sperm development and reproductive function
• CoQ10 to support mitochondrial energy production and antioxidant defense
• Omega-3 fatty acids to support cellular membrane health and overall reproductive wellness

Because sperm take approximately 70 to 90 days to mature, the choices made today can influence fertility outcomes several months from now. Supporting sperm health is about more than improving fertility. It is about helping create the healthiest possible foundation for future generations.