Causes of Infertility in Men

What Causes Male Infertility?

According to Urology Care Foundation, Male infertility is any health issue in a man that lowers the chances of his female partner getting pregnant. About 40 percent of infertility cases involve issues with the male partner, either as the sole cause or a contributing factor.

Male-factor infertility usually has to do with the quantity and quality of sperm in a man’s semen. Making mature, healthy sperm that can travel depends on many things. Problems can stop cells from growing into sperm. Problems can keep the sperm from reaching the egg. Even the temperature of the scrotum may affect fertility.

Sperm problems can be from traits you're born with. Lifestyle choices can lower sperm numbers. Smoking, drinking alcohol, and taking certain medications can lower sperm numbers. Other causes of low sperm numbers include long-term sickness (such as kidney failure), childhood infections (such as mumps), and chromosome or hormone problems (such as low testosterone).

Male fertility is a complex process

For men to be successful in getting your partner pregnant, the following must occur:

  • You must produce healthy sperm. Initially, this involves the growth and formation of the male reproductive organs during puberty. At least one of your testicles must be functioning correctly, and your body must produce testosterone and other hormones to trigger and maintain sperm production.

  • Sperm have to be carried into the semen. Once sperm are produced in the testicles, delicate tubes transport them until they mix with semen and are ejaculated out of the penis.

  • There needs to be enough sperm in the semen. If the number of sperm in your semen (sperm count) is low, it decreases the odds that one of your sperm will fertilize your partner's egg. A low sperm count is fewer than 15 million sperm per milliliter of semen or fewer than 39 million per ejaculate.

  • Sperm must be functional and able to move. If the movement (motility) or function of your sperm is abnormal, the sperm may not be able to reach or penetrate your partner's egg.

Medical or Anatomical Causes of Male Infertility

After sperm are produced in a man’s testicles, they travel through small tubes to mix with semen before being ejaculated from the penis. If something in a man’s anatomy blocks the flow of sperm to the semen, it may result in low sperm count or poor sperm quality, making it more difficult for pregnancy to occur.

One of the more common anatomical causes of male infertility is a varicocele, which is an enlarged vein within the scrotum. It is thought that the enlargement can impede blood flow and raise the temperature within the scrotum, causing reduced sperm production and poorer sperm quality.

Varicoceles are very common and do not always cause infertility in men. It is estimated that about 15 percent of the male population have varicoceles (including Dr. Parry – so men who have one are not alone).

Other physical defects contributing to male infertility include testicular torsion (twisting and swelling of a testicle which may cause permanent damage), retrograde ejaculation, undescended testicle, and damage or blockage in the ducts that carry sperm to the semen.

Erectile Dysfunction (Impotence) and male infertility

While ED doesn’t directly cause male infertility, they may have the same root causes and are often seen in conjunction with each other. Erectile dysfunction, or impotence, is when a man is unable to get or maintain an erection for intercourse. This can be due to underlying disorders such as diabetes or heart disease but may also occur due to psychological issues including depression and anxiety. Lifestyle factors such as drug and alcohol abuse can also affect a man’s ability to obtain and sustain an erection.

Erectile dysfunction is a symptom, not a disease, so treating the underlying cause of your erectile dysfunction can potentially resolve the struggle with infertility. ED certainly can be a contributing factor to male infertility because it gets in the way of ejaculation, which is required in order for the sperm to enter the vaginal canal and seek out the woman’s egg.

How Hormonal Disorders impact Male Infertility

The production of healthy sperm requires a proper balance of sex hormones in a man’s body. Disorders affecting the thyroid and pituitary glands, for example, can negatively impact the amount of testosterone and other reproductive hormones in a man’s body. This can in turn have a negative impact on sperm production.

Three male fertility hormones are crucial to driving the process of sperm production: Testosterone, Follicle-stimulating hormone (FSH), and Luteinizing hormone. The right balance of all three is necessary for healthy sperm and optimal male fertility.

Testosterone is responsible for the creation and growth of male sex organs (the penis and testes), and for the development of secondary sex characteristics during puberty, such as muscle growth, body hair, and a deeper voice.

Testosterone is produced within the testicles, by cells called Leydig cells. Testosterone is essential for some aspects of the process of creating sperm, known as spermatogenesis; specifically, it drives the division and differentiation of sperm cells. Low testosterone is known as hypogonadism, and may be caused by age or lifestyle factors.

Follicle stimulating hormone (FSH) is key to spermatogenesis. This hormone works closely with luteinizing hormone (LH) to produce sperm in the testes. Specifically, FSH is responsible for the function and maturation of the Sertoli cells, which are somatic (non-reproductive) cells in the testes that are essential for sperm production. Because of the big role that FSH plays in sperm production, low FSH can have serious consequences for sperm quality.

Luteinizing hormone (LH) is responsible for testosterone production in the testes. Specifically, LH stimulates the Leydig cells in the testes, which produce the testosterone that will help support sperm production. Like FSH, LH is produced in the pituitary gland.Similarly to low FSH, low LH can be caused by problems with the pituitary gland or excessive testosterone. Because LH drives the production of testosterone in the testes, a deficiency in LH can create a deficiency in testosterone, potentially impacting sex drive as well as fertility.

Common Signs of Infertility in Men

Changes in sexual desire

A man’s fertility is also linked with his hormone health. Changes in virility, often governed by hormones, could indicate issues with fertility.

Testicle pain or swelling

There are several different conditions that could lead to pain or swelling in the testicles, many of which could contribute to infertility.

Problems maintaining erection

A man’s ability to maintain an erection is often linked to his hormone levels. Reduced hormones may result, which could potentially translate into trouble conceiving.

Issues with ejaculation

Similarly, an inability to ejaculate is a sign that it might be time to visit a doctor.

Small, firm testicles

The testes house a man’s sperm, so testicle health is paramount to male fertility. Small or firm testicles could indicate potential issues that should be explored by a medical practitioner.

Lifestyle and Environmental Factors Effects on Male Infertility

Unhealthy lifestyle habits have been shown to negatively impact male fertility. Fertility experts also theorize that activities that increase the temperature of the scrotum, such as prolonged sitting, wearing tight pants or underpants, using a laptop computer and saunas and hot tubs, may decrease sperm production. Other lifestyle and environmental factors that can affect male fertility include:

  • Poor diet

  • Obesity

  • Smoking

  • Drugs & alcohol

  • Excessive stress

  • Exposure to environmental toxins such as industrial chemicals, lead or radiation.

There are many ways to treat male infertility

Treatments for male infertility are based on the underlying cause of the problem, or in the case of no identified problem, evidence-based treatments that improve fertility may be recommended.

Treatments can include:

  • surgery to correct or repair anatomic abnormalities or damage to reproductive organs,

  • use of medical procedures to deliver sperm to the woman,

  • fertilization of the egg in a laboratory, and

  • using a third party for donating sperm or eggs and/or carrying a pregnancy.

Medication can treat some issues that affect male fertility, including hormone imbalances and erectile dysfunction.

Surgery can be effective for repairing blockages in the tubes that transport sperm. Surgery can also be used for repair of varicocele. 2 Assistive reproductive technologies, such as in vitro fertilization, can be effective if other treatments do not restore fertility.

The best advice is do not suffer in silence. We are here to help you on your fertility journey. Just give us a call.

Related Information: Fertility Testing for Men



For an appointment, contact us online or call 833-767-7837